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Using Cost and Health Impacts to Prioritize the Targeted Testing of Tuberculosis in the United States
Using Cost and Health Impacts to Prioritize the Targeted Testing of Tuberculosis in the United States THADDEUS L. MILLER, MPH, PETER HILSENRATH, PHD, KRISTINE LYKENS, PHD, SCOTT J.N. MCNABB, PHD, PATRICK K. MOONAN, DRPH, AND STEPHEN E. WEIS, DO
PURPOSE: Evaluation improves efficiency and effectiveness. Current U.S. tuberculosis (TB) control policies emphasize the treatment of latent TB infection (LTBI). However, this policy, if not targeted, may be inefficient. We determined the efficiency of a state-law mandated TB screening program and a non statelaw mandated one in terms of cost, morbidity, treatment, and disease averted. METHODS: We evaluated two publicly funded metropolitan TB prevention and control programs through retrospective analyses and modeling. Main outcomes measured were TB incidence and prevalence, TB cases averted, and cost. RESULTS: A non state-law mandated TB program for homeless persons in Tarrant County screened 4.5 persons to identify one with LTBI and 82 persons to identify one with TB. A state-law mandated TB program for jail inmates screened 109 persons to identify one with LTBI and 3274 persons to identify one with TB. The number of patients with LTBI treated to prevent one TB case was 12.1 and 15.3 for the homeless and jail inmate TB programs, respectively. Treatment of LTBI by the homeless and jail inmate TB screening programs will avert 11.9 and 7.9 TB cases at a cost of $14,350 and $34,761 per TB case, respectively. CONCLUSIONS: Mandated TB screening programs should be risk-based, not population-based. Non mandated targeted testing for TB in congregate settings for the homeless was more efficient than statelaw mandated targeted testing for TB among jailed inmates. Ann Epidemiol 2006;16:305–312. Ó 2006 Elsevier Inc. All rights reserved. KEY WORDS:
Tuberculosis, Prevention, Public Health, Targeted Testing, Health Economics, Evaluation.
INTRODUCTION Health care in the United States is in crisis (1). Many agree that the current trajectory of health care costs threatens future access to affordable health care. Despite spending a greater proportion of its gross domestic product for health care than other industrialized countries, the US health care system underperforms when measured by important health impacts (e.g., decreased infant mortality or increased life expectancy). Improving the efficiency of health spending, especially ensuring that benefits justify costs, is a key to resolving this crisis. However, strategies to identify the best use of limited resources remain controversial (2). One strategy is to perform cost-effectiveness analysis (CEA) from a societal perspective (3). Systematic use of CEA to determine From the Department of Medicine, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX (T.L.M., P.H., K.L., P.K.M., S.E.W); School of Public Health, Fort Worth, TX (T.L.M., P.H., K.L., P.K.M., S.E.W); Centers for Disease Control and Prevention, Atlanta, GA (S.J.N.M); and Tarrant County Health Department, Fort Worth, TX (S.E.W.). Address correspondence to: Stephen E. Weis, DO, Department of Medicine, University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Blvd, Fort Worth, TX 76107. Tel.: (817) 321-4937; fax: (817) 321-4920. E-mail: [email protected]. Received April 3, 2005; accepted July 5, 2005. Ó 2006 Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010
insurance coverage decisions is an elusive goal (4). However, informed decision making does not always require a full CEA. Even in the context of disease elimination, such as tuberculosis (TB) prevention and control in the United States, public health programs should determine practical strategies to provide the most efficient prevention and control impacts. TB remains a public health problem in the United States despite historically low prevalence. In 2004, the United States had 14,511 new reported TB cases, an all-time low (5, 6). This trend caused the Centers for Disease Control and Prevention (CDC) to reevaluate the US TB elimination strategy and recommend targeted testing of specific high-risk populations (Table 1) (7, 8). Identifying and treating persons with latent TB infection (LTBI) is important to this strategy. Additionally, the Institute of Medicine recommended the development of more effective methods for identifying and treating persons with LTBI, but do not provide guidelines on how best to do so (14). Experts generally accept that homeless and jailed persons in the United States are at increased risk for infection with TB (15–25). Many recommendations identify these population groups for TB prevention and control efforts to decrease ongoing TB transmission (21–25). These recommendations target test those most likely to benefit from and comply with treatment recommendations (24, 25). However, mandated 1047-2797/06/$–see front matter doi:10.1016/j.annepidem.2005.07.053
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Selected Abbreviations and Acronyms CEA Z cost-effectiveness analysis TB Z tuberculosis LTBI Z latent tuberculosis infection CDC Z Centers for Disease Control and Prevention TST Z tuberculin skin test TCPHD Z Tarrant County Public Health Department RIF/PZA Z rifampin/pyranazimide
TB targeted testing in specific populations varies across jurisdictions and may not reflect efficient practices. When targeted-testing strategies must be prioritized, their relative cost efficiencies should be considered. In Texas, active TB case-finding is a state-law–mandated program for inmates in jails with population sizes greater than 100 (26). Although this law does not mandate screening for or treatment of LTBI, this intervention does further TB prevention and control goals and is performed routinely in Tarrant County jails (27, 28). However, there are fewer data to guide strategies for TB prevention and control programs in jails than prisons or congregate living facilities for the homeless (19, 21). Nevertheless, TB outbreaks in jails capture public attention and require clearly articulated data-driven strategies (27–36). We compared costs and health impacts between two TB programs in Tarrant County: the correctional health TB surveillance program and a homeless shelter outreach program. We focus on the health impacts of each program designed to identify and treat LTBI. One additional outcome of this study is an economic tool that can be used to evaluate various strategies for TB prevention and control.
METHODS We conducted a retrospective comparison of the cost and health impacts between the Tarrant County, TX, homeless TB screening program and the jail TB screening program. This evaluation was part of the Tuberculosis Epidemiologic Studies Consortium Project, New Model for Assessing
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Tuberculosis Surveillance and Action Performance and Cost, funded by the CDC. The unit of study was the public health program; no individual patient information was used. The study period for the jail program was 335 days from December 19, 2001, through December 18, 2002. Data used for analysis of the homeless program were collected for calendar year 2003. Comparisons are made based on patients with TB diagnosed in the study period and having known treatment duration. Treatment durations reflect all treatment, including that known to occur in other settings. Reports from all TB screening programs in county jail facilities in Tarrant County were included in this evaluation. In Tarrant County, jail inmates are administered a Mantoux tuberculin skin test (TST) with 5 tuberculin unit–strength purified protein derivative. Those with a clearly documented prior positive TST result are not retested. A TST reading of 10 mm or greater induration is defined as a positive result. If there is a history of TB exposure or human immunodeficiency virus infection, positive is defined at 5 mm or greater. All individuals with a newly positive TST result, a previous positive TST result, or symptoms of TB-related illness undergo additional evaluation by medical personnel at the facility. Treatment of LTBI is offered as clinically appropriate. Medically licensed staff directly observed all TB therapy. Jail program data were abstracted from monthly reports compiled by Tarrant County Public Health Department (TCPHD) personnel. These reports included number of evaluations, TST results, radiographs, cultures, diagnosis, and TB risk information (e.g., TST converter, human immunodeficiency virus status, regimen and amount of TB treatment, and final status). We gathered population information from the US Census Bureau (37). The homeless program is an outreach effort by the TCPHD in which homeless persons in a congregate setting are targeted for TB testing. The program includes on-site TB symptom check, chest radiograph, TST, and medical evaluation. TST was performed as described. Area residents had TB exposure, and a positive TST result was defined as 5 mm or greater. TCPHD personnel, who were available
TABLE 1. Comparison of populations at risk for tuberculosis, United States and Tarrant County, Texas, 2002 (6, 7, 9–13) United States Variable Total Homelessa Foreign-born Local jailb a
Population (%) 280,540,330 800,000–3,500,000 (0.3%–1.3%) 32,453,000 (11.6%) 652,082 (0.2%)
No. of cases reported
Tarrant County, Texas Incidence rate (/100,000 population)
Population (%)
No. of cases reported
Incidence rate (/100,000 population)
5.2 110.3–25.2 23.1 Unknown
1,446,219 4,375–8,631 (0.3%–0.6%) 206,061 (14.3%) 3119 (0.2%)
109 13 53 7
7.2 297.1–150.6 26 31c
15,075 883 7659 Unknown
Range is point estimate of the number of homeless at any time in 1 year. Average daily population in 2002. Tuberculosis incidence rate based on number screened.
b c
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for 5 evening hours Monday through Friday, observed treatment on site. Personnel observing TB therapy were experienced in working with homeless persons and successfully completed the CDC core TB training modules, but did not have medical licenses (38). Training included TB symptoms, side effects, directly observed preventive therapy, follow-up, tracking protocols, and safety strategies. In addition, personnel were supervised by public health nurses and physicians. Patients received an incentive for keeping medication appointments, including dietary supplements or fast-food coupons. Resumption of TB therapy for interruptions of less than 3 months did not require reevaluation. No costs accrued to the homeless shelter or patients (39). Costs and activities associated with the detection and treatment of TB in these two settings were estimated as previously described for patients with uncomplicated active TB and LTBI (40). They were adjusted to reflect current conditions and TB treatment recommendations (41–45). Treatment and professional costs were estimated at the midpoint of Medicare’s national average allowance and mean fee for non-Medicare charges, and average wholesale price for drugs was used (40). Costs were adjusted to 2003 US dollars (45). The sums of screening and treatment costs were used for comparison of programs. Costs of negative screening results were adjusted proportionally to the number of LTBI and TB diagnoses made. Estimated hospitalization rates and costs were adjusted to the region (46). We did not consider costs for contact investigations, patient expenses, facilities, administration, or other program costs. Treatment regimens for LTBI were described according to medications used, dosing, and proportion of a full course of treatment completed. We categorized treatment of LTBI as either isoniazid therapy (‘‘long course’’) or other drug combination (‘‘short course’’). Costs and disease risk
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reduction associated with LTBI treatment reflected the duration of treatment (47–57). Therapy was observed, so we assumed ‘‘completer-complier’’ efficacy and cumulative effect for multiple sessions or regimens of LTBI treatment (58). Dosing and duration information were converted to a standard metric reflecting the proportion of recommended treatment for each regimen. We modeled risk reduction from LTBI treatment as a cumulative reduction of disease risk for risk groups from the annual expected risk (47–57). Within the model, recent converters remained at increased risk for 1 year, then their risk decreased to that of remotely infected (47–57). Navigate to http://www.hsc.unt.edu/ intmed/Documents/risk%20reduction%20calculator.xls to access our disease reduction estimation tool. Differences in proportions, medians, and means were calculated. All statistical tests were two sided, with levels of 0.05 or less considered significant. Descriptive statistics were compiled and calculations were performed using Microsoft Excel 2002 (Microsoft Corp., Redmond, WA), SPSS, version 12 (SPSS Inc., Chicago, IL), and STATA 8.0 (StataCorp LP, College Station, TX).
RESULTS During 335 days in 2002, a total of 22,920 jailed inmates underwent state-law–mandated TB screening in the Tarrant County jail system (Table 2). The result of this targeted testing was identification of 14 TB suspects, TB subsequently was diagnosed in seven of these patients, and 211 patients were prescribed treatment for LTBI. A second non– state-law–mandated TB program screened homeless persons in Tarrant County. In this program, 822 homeless persons were screened and 34 TB suspects were identified, TB
TABLE 2. Comparison of the yield of TB infected and diseased patients, by screening program, Tarrant County, Texas, 2002 No. of patients (%)
Screened TST placed Previous positive result Positive TST resultb Treatment for LTBI prescribedc Treated for TB Lost unread No. screened/LTBI No. screened/TB case Screenings/treatmentd
Cost, 2003 (US $)a
per 100,000
Homeless
Jail
p
Homeless
Jail
Homeless
Jail
822 778 (94.7) 63 (7.7) 127 (15.5) 181 (22) 10 (1.2) 245 (29.8) 4.5 82.2 5.7
22,920 21,778 (95) 1142 (5) 303 (2) 211 (0.9) 7 (0.03) 6760 (31.1) 108.7 3274 140
0.179 0.001 !0.001 !0.001 !0.001 0.356 d d d
d d 7664 15,456 22,019 1217 29,817 22,222 1217 d
d d 4983 1322 951 31 29,568 920 31 d
$54,334 d d d $809 $7835 d $300 $5433 $377
$245,244 d d d $774 $7835 d $1163 $35,035 $1498
LTBI, latent tuberculosis infection; TB, tuberculosis; TST, tuberculin skin test. a Cost reflects average cost per treatment, per patient; cost per number screened reflects screening costs required to yield one LTBI or TB diagnosis. Treatment criteria include exposure, symptoms, or other factors not limited to positive screening. b Proportion of tests that were read. c Diagnosis of LTBI may be caused by factors other than positive TST (e.g., exposure, previous positive TST result with inadequate treatment). Number of LTBIs includes 24 homeless program suspects and 7 jail program suspects in whom TB was ruled out. d Number and cost of screenings required to initiate one treatment.
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subsequently was diagnosed in 10 of these patients, and 181 patients were prescribed treatment for LTBI. TB suspects not confirmed as having TB were treated for LTBI. An estimate of the resources required to avert one TB case through screening and treatment of LTBI is a function of the number necessary to screen to detect and treat patients with LTBI and duration of treatment (Table 3). In the homeless program, 69 screenings were required to avert one TB case, 5.7 screenings were needed to initiate one LTBI treatment, and 12.1 treatments were required to avert one case. The jail program found fewer TB cases and required more treatments per TB case averted, resulting in 2142 screenings to avert one TB case. The homeless person TB program cost $14,350 per TB case prevented, and the jail inmate TB program cost $34,761 per TB case prevented. The larger estimated risk reduction achieved by treatment of LTBI in the homeless person TB program will result in 150% more TB averted than will the jail inmate TB program (11.9 versus 7.9 TB cases averted, respectively). LTBI treatments given within the homeless program yielded greater overall levels of completion than the jail program (median homeless program treatment completed Z 0.72 treatment course [midspread Z 0.31 to 1] versus median jail program treatment completed Z 0.26 treatment course [midspread Z 0.06 to 0.89]). Every 12.1 treatments of LTBI initiated in the homeless program and 15.3 treatments
TABLE 3. Outcomes of treatment for LTBI in the homeless and jail screening programs, Tarrant County, Texas, 2002 to 2003 Homeless
Jaila
No. of patients (%)
No. of patients (%)
Treatment for LTBI prescribed 181 Total treated 143 Refused or lost 38 (26.6) Short course 77 (42.5) Long course 66 (36.5) 0.72 (0.31–1) Median treatment completed (midspread)b TB cases preventedc 11.9 Average cost for LTBI treatment 809 (2003 US $)d No. of LTBI treatments 12.1 to prevent 1 TB case Screenings to prevent 1 TB case 69 Screening cost per case preventede ($) 4561 Cost per case preventede ($) 14,350
211 121 47 (22.3) 39 (32.2) 82 (67.8) 0.26 (0.06–0.89) 7.9 774 15.3 2,142 22,919 34,761
TB, tuberculosis; LTBI, latent tuberculosis infection. a Excludes those with unknown treatment durations (w20%). b Median of recommended therapy, short and long course combined in full course equivalents. c From risk reduction during 20 years. d Cost for average proportion completed adjusted to reflect treatment regimen. e Total cost to detect and treat sufficient LTBI to prevent one case and excludes 43 cases with duration unknown in jail cohort.
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initiated in the jail program resulted in a sufficient risk reduction to prevent one patient from developing TB. Estimated individual screening and treatment costs were slightly greater in the homeless population, largely because of the use of a chest radiograph added to the TST for every patient at the initial screening. The cost per patient diagnosed was much greater in the jail program than the homeless program (TB Z $35,035 versus $5433 and LTBI Z $1163 versus $300, respectively). There were no differences in outcomes or estimated treatment costs for patients with TB in the jail and homeless programs. In both, standard treatment regimens were prescribed, and all completed therapy. We predict that LTBI treatment in the homeless population achieved 74% of the current maximum possible disease reduction, considering its risk groups (Table 4). The jail inmate population achieved 52% of the maximum possible disease reduction. When LTBI incidence is decreased by 50% and 75% in sensitivity analyses, we estimate minimum costs per active case averted range from $21,082 to $71,514 if all treatment is completed and $28,943 to $137,306 with treatment completed as found. Within the jail, 6760 persons did not have their TST read because of release. Our findings suggest that had a test been available to more rapidly diagnose TB, and additional two TB cases and 62 latent or suspected TB infections would have been discovered. A similar proportion of TSTs were not read among homeless persons. We predict that another three TB cases and 56 latent or suspected TB infections would have been discovered if all TSTs were read.
DISCUSSION Using data routinely accessible by local health agencies, we found that a homeless TB screening program was more than 21 times more effective in identifying LTBI and almost 40 times more effective in detecting TB than a state-law–mandated jail TB screening program. The homeless program averted more cases of TB at less cost. These results show that mandated TB screening should be justified on population risk. Determining population risk does not require extensive research, but often can be done by using sampling or preexisting data. Risk-based TB screening programs that include congregate living facilities for homeless persons should be highly effective in averting TB disease. Both targeted screening programs detected much greater morbidity than if unrestricted broad-population screening were used. In addition, our data provide validation to guidelines recommending targeted testing for TB.
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TABLE 4. Sensitivity analysis showing benefits and cost per TB case averted when the diagnosis of LTBI is made, Tarrant County, Texas, 2002 to 2003 LTBI diagnosis made Homeless, n Z 143 Jail, n Z 121 Homeless, n Z 72 Jail, n Z 61 Homeless, n Z 36 Jail, n Z 30
Maximum benefita
Actual benefitb
When LTBI is as found 16.2 11.9 15.2 7.9 When LTBI is decreased 50% 8.1 5.9 7.6 4 When LTBI is decreased 75% 3.9 3 3.8 2
LTBI incidence (/100,000 population)
Cost per TB case avertedc (2003 US $)
2202 92
With maximum benefit 10,541 18,067
Actual 14,350 34,761
1101 46
21,082 36,133
28,943 68,653
551 23
43,786 71,514
56,922 137,306
Total actual cost (2003 US $)d 170,765 274,613
LTBI, latent tuberculosis infection; TB, tuberculosis. a In cases averted over time where risk factors remain constant, maximum benefit implies 100% compliance with recommended treatment. b Actual benefit implies benefit with treatment completion rates as found. Screened persons: 828 homeless screened, 22,920 jail screened. c Cost to detect and treat sufficient LTBI to avert one case. Costs represent screening and treatment for LTBI and TB suspects only. d Excludes cost for 43 inmates with treatment duration unknown.
The growth in the cost of US health care is not sustainable. There is growing recognition that greater efficiency in the health sector will involve tough decisions about priorities, with resource allocation going to the most efficient activities (1–4). These decisions are difficult to make for diseases for which the goal is elimination (14). Decreasing TB infection in the general population makes traditional case-finding increasingly expensive at the margin, requiring new approaches (8, 17, 19–24). Modeling has been used to attempt to identify the best TB control practices (52, 56, 57). We combined these techniques with program data to compare for the first time the relative effectiveness of two TB programs. Homelessness predisposes people with LTBI to progress to TB, and TB in this population has been identified as a major source of morbidity in metropolitan areas across the United States (59–64). Studies of TB isolates from homeless persons detected unsuspected TB transmission across jurisdictional borders and between homeless and nonhomeless persons and found transmission of multidrug-resistant TB (62, 65). Estimates of the national homeless population in the late 1990s varied from 800,000 to 3,500,000 persons (66). Assuming TB morbidity similar to that found in the Tarrant County homeless program, the national homeless population may represent a reservoir of 22,019 patients with LTBI per 100,000 screened. Per 100,000 similar screenings and LTBI treatments, we estimate an investment of $20,806,148 in detection and treatment would identify 1217 persons with TB in the screening year and avert 1449 cases. Likewise, 100,000 jail inmates screened would result in identification of 31 TB cases and avert 47 cases at a cost of $1,633,767. The ultimate cost or savings from such efforts will require study of the full cost of TB, but our findings indicate that achieving the goal of national TB elimination will require innovative programs in homeless and other high-risk populations.
An insight from a study of strategies for TB risk reduction was that access to care is more important to reducing TB and deaths in the homeless than improving effectiveness of therapy (19). The TCPHD homeless program is designed to be maximally accessible. This may contribute to the high acceptance and completion of treatment for LTBI in that program. Seventy-nine percent of homeless patients started LTBI therapy, and the median proportion of LTBI therapy completed was 72%. In a study of 4 years of LTBI treatment in homeless persons in Denver, only 21% with LTBI were started on therapy and only 28% of those completed therapy (69). In an LTBI treatment adherence study, homeless persons randomly assigned to usual care in San Francisco received a median of 2 months of isoniazid therapy, with similar results found in other studies (67–70). An unexpected finding in our study is that the Tarrant County homeless population was more stable in terms of successful therapy than the jail population. Using monitoring and evaluation to measure cost and performance in TB control programs has been described previously (71). That analysis identified wasted resources and missed opportunities for TB control within a county jail system (71). Our study describes how monitoring and evaluation can suggest more efficient use of resources among many choices for public health action. At midyear 2003, there were 691,301 jailed inmates held nationally, and that number is increasing (72). Turnover is high, with jail inmates usually confined a year or less (72). Although there are few data on results of TB screening in jails, there is evidence of TB transmission within jails and from jails into the community (15, 16, 27–35, 72–74). It was suggested that TB testing of jail inmates has a major role in reducing TB in the community (30). In the Tarrant County jail program, we found a TB prevalence of 31 cases per 100,000 and an LTBI prevalence of 921 cases per
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100,000. This emphasizes the importance of the jail as a reservoir of TB and a location where targeted testing and treatment of TB can occur, but inmate turnover and treatment follow-up challenges remain. We recognize that we do not include all costs associated with TB, including those generated by contact investigations, secondary transmission, and patient costs (50, 51, 58, 75). All such costs are assumed to be similar in this study. We therefore underestimated the complete cost of a TB case by failing to consider these additional costs and hence underestimated the full savings from averting a case of TB (50, 75). Some differences exist between the jail inmate and homeless person cohorts that may affect comparability. Existing programmatic data were collected, allowing only gross demographic comparisons of the groups. The study periods were not concurrent. During the time the jail program was analyzed, rifampin/pyranazimide (RIF/PZA) therapy was not known to carry undue risk and was recommended as appropriate for short-duration LTBI therapy (76). During the period the homeless program was analyzed, RIF/PZA therapy rarely was used because of potential side effects. However, these differences do not affect our conclusions because the RIF/PZA combination therapy has been shown to increase treatment completion compared with isoniazid therapy. Lack of complete information on dosing resulted in approximately 20% of jail LTBI treatments being excluded from analysis; however, these missing data were random, with no indication that this information would change our findings. TB screening is recommended in many situations by guidelines and mandated in some by legal statute (15–26). Decisions about populations required to undergo TB screenings are made at a political level for many reasons. The protection of public health and protection of prisoners from exposure to potentially fatal preventable illnesses often must be considered before questions of efficiency. Wide variations in TB risks and public health infrastructures make it difficult to generalize the experience in Tarrant County to the United States, and both inmate and homeless populations offer challenges for TB control that have been well described (8, 9, 14–21, 24, 27–36). Finding relative efficiency in the homeless program in Tarrant County does not require that jail programs be abandoned for homeless programs. Rather, our findings suggest that strategies for TB elimination should ensure efficient use of resources within communities through an evaluation component. We illustrate how monitoring and evaluation can help set priorities to maximize return on spending for TB interventions. By directing prevention and control programs toward reservoirs of latent disease and populations for which risk makes them effective and efficient screening targets, we can improve our progress toward achieving TB elimination in the United States.
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The authors gratefully acknowledge the contributions to this work made by Karen Kardaras, Maureen Wilce, and Bridget Young.
REFERENCES 1. Walker DM. Health Care System Crisis: Growing Challenges Point to Need for Fundamental Reform. Government Accountability Office. Available at: http://www.gao.gov/cghome/hccrisis/. Accessed November 20, 2004. 2. Gillick MR. Medicare coverage for technological innovations-time for new criteria? N Engl J Med. 2004;350:2199–2203. 3. Russell LB, Gold MR, Siegel JE, Daniels N, Weinstein MC. The role of cost-effectiveness analysis in health and medicine. JAMA. 1996;276: 1172–1177. 4. Tunis SR. Why Medicare has not established criteria for coverage decisions. N Engl J Med. 2004;350:2196–2198. 5. Centers for Disease Control and Prevention. Reported Tuberculosis in the United States, 2003. Atlanta, GA: CDC; 2004. 6. Centers for Disease Control and Prevention. Fact Sheet: Tuberculosis in the United States, 2004. Available at: http://www.cdc.gov/od/oc/media/ pressrel/fs050317.htm. Accessed June 22, 2005. 7. Centers for Disease Control and Prevention. Tuberculosis morbidity among U.S.-born and foreign-born populationsd2000. MMWR Morbid Mortal Wkly Rep. 2002;51:101–104. 8. Centers for Disease Control and Prevention. Tuberculosis elimination revisited: Obstacles, opportunities, and a renewed commitment. MMWR Morbid Mortal Wkly Rep. 1999;48:No. RR–9:1–13. 9. Martin K. Tarrant County Community Development Division, personal communication. December 14, 2004. 10. 2000 US Census American Community Survey, 2002. Available at: www.census.gov. Accessed February 1, 2004. 11. Henry J. Kaiser Foundation. 2400 Sand Hill Road, Menlo Park, CA. Long-Term Care: Medicaid’s Role and Challenges. Publication no. 2172. Henry J. Kaiser Foundation; 1999. 12. US Department of Justice, Office of Justice Programs. Prison and Jail Inmates at Midyear, 2002. Bureau of Justice Statistics Bulletin, April 2003. Available at: http://www.ojp.usdoj.gov/bjs/pub/pdf/pjim02.pdf. Accessed January 11, 2005. 13. US Census Bureau. Foreign-Born Population of the United States Current Population SurveydMarch 2002 Detailed Tables (PPL-162). Available at: www.census.gov/prod/2003pubs/p20-539.pdf. Accessed February 26, 2004. 14. Institute of Medicine. Ending Neglect: The Elimination of Tuberculosis in the United States. Washington, DC: National Academy; 2000. 15. Wilcock K, Hammett TM, Widom R, Epstein J. Tuberculosis in Correctional Facilities, 1994–1995. National Institute of Justice Research in Brief, US Department of Justice, Office of Justice Programs; US Department of Justice, Washington, DC 1996. 16. Hammett TM, Harmon P, Maruschak LM. 1996–1997 Update: HIV/ AIDS, STDs, and TB in Correctional Facilities. US Department of Justice, Office of Justice Programs; US Department of Justice, Washington, DC 1999. 17. Brewer TF, Heymann SJ, Krumplitsch SM, Wilson ME, Colditz GA, Fineberg HV. Strategies to decrease tuberculosis in US homeless populations: A computer simulation model. JAMA. 2001;286:834–842. 18. Moonan PK, Bayona M, Quitugua TN, Oppong J, Dunbar D, Jost Jr KC, et al. Using GIS technology to identify areas of tuberculosis transmission and incidence. Int J Health Geographics. 2004;3:23–33. 19. Rendleman NJ. Mandated tuberculosis screening in a community of homeless people. Am J Prev Med. 1999;17:108–113. 20. Centers for Disease Control and Prevention. Prevention and Control of Tuberculosis in Correctional Facilities. Atlanta, GA: CDC; 1995.
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21. Centers for Disease Control and Prevention. Screening for tuberculosis and tuberculosis infection in high risk populations: Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1994;44:19–34. 22. Horsburgh CR Jr. Priorities for the treatment of latent tuberculosis infection in the United States. N Engl J Med. 2004;350:2060–2067. 23. Centers for Disease Control and Prevention. Targeted tuberculin testing and treatment of latent tuberculosis infection. MMWR Morbid Mortal Wkly Rep. 2000;49(No. RR-6):1–54. 24. Centers for Disease Control and prevention. Prevention and control of tuberculosis in US communities with at-risk minority populations: Recommendations of the Advisory Council for the Elimination of Tuberculosis and Prevention and control of tuberculosis among homeless persons: Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1992;41(RR-5):1–11. 25. Essential components of a tuberculosis prevention and control program. Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1995;44:1–16. 26. Texas Health and Safety Code, Title 25, Part I, Chapter 97, Sub-Chapter H. Available at: http://info.sos.state.tx.us/pls/pub/readtac$ext.ViewTAC? tac_view Z 5&ti Z 25&pt Z 1&ch Z 97&sch Z H&rl Z Y. Accessed December 1, 2004. 27. King L, Geis G. Tuberculosis transmission in a large urban jail. JAMA. 1977;237:791–792. 28. Jones TF, Schaffner W. Miniature chest radiograph screening for tuberculosis in jails: A cost-effectiveness analysis. Am J Respir Crit Care Med. 2001;164:77–81. 29. Lobato MN, Roberts CA, Bazerman LB, Hammett TM. Public health and correctional collaboration in tuberculosis control. Am J Prev Med. 2004; 27:112–117. 30. Hammett TM, Harmon MP, Rhodes W. The burden of infectious disease among inmates of and releasees from US correctional facilities, 1997. Am J Public Health. 2002;92:1789–1794. 31. White MC, Tulsky JP, Portillo CJ, Menendez E, Cruz E, Goldenson J. Tuberculosis prevalence in an urban jail: 1994 and 1998. Int J Tuberc Lung Dis. 2001;5:400–404.
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41. US Department of Labor. Bureau of Labor Statistics Occupational Employment Statistics, May 2003. Available at: http://www.bls.gov/oes/2003/may/ oes211091.htm#nat. Accessed November 22, 2004. 42. US Department of Labor. Bureau of Labor Statistics. Consumer Price Index Urban Wage Earners and Clerical Workers, Medical Care US City Average. Available at: http://data.bls.gov/cgi-bin/surveymost. Accessed November 22, 2004. 43. Centers for Disease Control and Prevention. Treatment of tuberculosis. MMWR Morbid Mortal Wkly Rep. 2003;52:1–88. 44. US Department of Labor. Bureau of Labor Statistics. CPI Urban Wage Earners and Clerical Workers, Medical Care Services US City Average. Available at: http://data.bls.gov/cgi-bin/surveymost. Accessed November 22, 2004. 45. US Department of Labor, Bureau of Labor Statistics. CPI for Medical Care Commodities. Available at: http://www.bls.gov/news.release/cpi.t05.htm. Accessed November 22, 2004. 46. Taylor Z, Marks SM, Rios Burrows NM, Weis SE, Stricof RL, Miller B. Causes and costs of hospitalization of tuberculosis patients in the United States. Int J Tuberc Lung Dis. 2000;4:931–939. 47. Gordin F, Chaisson RE, Matts JP, Miller C, de Lourdes Garcia M, Hafner R, et al. Rifampin and pyrazinimide vs. isoniazid for prevention of tuberculosis in HIV-infected persons: An international randomized trial. JAMA. 2000;283:1445–1450. 48. IUAT Committee on Prophylaxis. Efficacy of various durations of isoniazid preventive therapy for tuberculosis: Five years of follow-up in the IUAT trial. Bull World Health Org. 1982;60(44):555–564. 49. Ferebee SHE. Controlled chemoprophylaxis trials in tuberculosis: A general review. Adv Tuberc Res. 1970;17:28–106. 50. Comstock GW. How much isoniazid is needed for prevention of tuberculosis among immunocompetent adults? Int J Tuberc Lung Dis. 1999; 10:847–850. 51. Javitz HS, Ward M. Value of antimicrobials in the prevention and treatment of tuberculosis in the United States. Int J Tuberc Lung Dis. 2002;6:275–288. 52. Taylor Z. The cost-effectiveness of screening for latent tuberculosis infection. Int J Tuberc Lung Dis. 2000;4(suppl):S127–133.
32. Tulsky JP, White MC, Dawson C, Hoynes TM, Goldenson J, Schecter G. Screening for tuberculosis in jail and clinic follow-up after release. Am J Public Health. 1998;88:223–226.
53. Salpeter EE, Salpeter SR. A mathematical model for the epidemiology of tuberculosis, with estimates of the reproductive number and infectiondelay function. Am J Epidemiol. 1998;47:398–406.
33. White MC, Tulsky JP, Reilly P, MacIntosh HW, Hoynes TM, Goldenson J. A clinical trial of financial incentive to go to the tuberculosis clinic for isoniazid preventive therapy for released jail inmates. Int J Tuberc Lung Dis. 1998;2:506–512.
54. Snyder DC, Paz AE, Moehle-Boetani JC, Fallstad R, Black RL, Chin DP. Tuberculosis prevention in methadone maintenance clinics: Effectiveness and cost-effectiveness. Am J Respir Crit Care Med. 1999;160: 178–185.
34. Lincoln T, Brannan GL, Lynch V, Conklin TJ, Clancey T, Rose TN, et al. Completing tuberculosis prophylaxis in jail: Targeting treatment and comparison of rifampin/pyrazinamide with isoniazid regimens. Int J Tuberc Lung Dis. 2004;8:306–311.
55. Snyder DC, Chin D. Cost-effectiveness analysis of directly observed therapy for patients with tuberculosis at low risk for treatment default. Am J Respir Crit Care Med. 1999;160:582–586.
35. Reichman LB. On target. A tuberculosis control strategy whose time has come. Ann Intern Med. 1999;131:617–618. 36. Jones TF, Craig AS, Valway SE, Woodley CL, Schaffner W. Transmission of tuberculosis in jails. Ann Intern Med. 1999;131:557–563. 37. US Census Bureau. US Census, 2000. Available at: http://quickfacts. census.gov/qfd/states/48/48439.html. Accessed February 1, 2004. 38. Centers for Disease Control and Prevention. Self Study Modules on Tuberculosis 1-5, Course #SS3035. National Center for HIV, STD, and TB Prevention, Division of Tuberculosis Elimination. Available at: http:// www.phppo.cdc.gov/PHTN/tbmodules/Default.htm. Accessed December 20, 2004. 39. Moonan PK, Bayona M, Quitugua TN, Oppong J, Burgess G, Hines NL, et al. Targeted Screening for Tuberculosis Combining GIS and Genotyping Technology. Presented at American Public Health Association Annual Meeting, San Francisco, CA, November 15, 2003. 40. Qualls N. Centers for Disease control and prevention, personal communication. December 14, 2004.
56. Salpeter SR, Sanders GD, Salpeter EE, Owens DK. Monitored isoniazid prophylaxis for low-risk tuberculin reactors older than 35 years of age: A risk-benefit and cost-effectiveness analysis. Ann Intern Med. 1997;127:1051–1061. 57. Rose DN. Benefits of screening for latent Mycobacterium tuberculosis infection. Arch Intern Med. 2000;160:1513–1521. 58. Floyd K. Costs and effectivenessdThe impact of economic studies on TB control. Tuberculosis 2003;83:187–200. 59. Rendleman NJ. Mandated tuberculosis screening in a community of homeless people. Am J Prev Med. 1999;17:108–113. 60. Barnes PF, Yang Z, Pogoda JM, Preston-Martin S, Jones BE, Otaya M, et al. Foci of tuberculosis transmission in central Los Angeles. Am J Respir Crit Care Med. 1999;159:1081–1086. 61. Lathan M, Ntaate Musaka L, Hooper N, Golub J, Baruch N, Mucahy D, et al. Cross-jurisdictional transmission of Mycobacterium tuberculosis in Maryland and Washington, DC, 1996-2000, linked to the homeless. Emerg Infect Dis. 2002;8:1249–1251.
312
Miller et al. FINDING EFFICIENCY AMONG TB CONTROL STRATEGIES
62. Munsiff S, Bassoff T, Nivin B, Li H, Sharma A, Bifani P, et al. Molecular epidemiology of multidrug-resistant tuberculosis, New York City, 19951997. Emerg Infect Dis. 2002;8:1230–1238. 63. Centers for Disease Control and Prevention. Public health dispatch: Tuberculosis outbreak among homeless personsdKing County, Washington, 2002-2003. MMWR Morbid Mortal Wkly Rep. 2003;52: 1209–1210. 64. Bock NN, Metzger BS, Tapia JR, Blumberg HM. A tuberculin screening and isoniazid preventive therapy program in an inner-city population. Am J Respir Crit Care Med. 1999;159:295–300. 65. French AL, Welbel SF, Dietrich SE, Mosher LB, Breall PS, Paul WS, et al. Use of DNA fingerprinting to assess tuberculosis infection control. Ann Intern Med. 1998;129:856–861. 66. Burt ML. What Will It Take to End Homelessness? Urban Institute. 2001. Available at: http://www.urban.org/url.cfm?ID Z 310305. Accessed December 1, 2004. 67. Kong PM, Tapy J, Calixto P, et al. Skin-test screening and tuberculosis transmission among the homeless. Emerg Infect Dis. 2002;8: 1280–1284. 68. Tulsky JP, Pilote L, Hahn JA, Zolopa AJ, Burke M, Chesney M, et al. Adherence to isoniazid prophylaxis in the homeless: A randomized controlled trial. Arch Intern Med. 2000;160:697–702. 69. Burman WJ, Cohn DL, Rietmeijer CA, Judson FN, Sbarbaro JA, Reves RR. Noncompliance with directly-observed therapy for tuberculosis:
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Epidemiology and effect on the outcome of treatment. Chest. 1997; 111:1168–1173. 70. Pablos-Me´ndez A, Knirsch CA, Barr RG, Lerner BH, Frieden TR. Nonadherence in tuberculosis treatment: Predictors and consequences in New York City. Am J Med. 1997;102:164–170. 71. McNabb SJN, Surdo A, Redmond A, Cobb J, Wiley J, Chakrabarti S, et al. Applying a new conceptual framework to evaluate public health surveillance and action, Hillsborough County, Florida, 2002. Ann Epidemiol. 2004;14:640–645. 72. US Department of Justice, Office of Justice Programs. Bureau of Justice Statistics Profile of Jail Inmates, 2002. Available at: www.ojp.usdoj.gov/ bjs/. Accessed December 12, 2004. 73. Chaves F, Dronda MD, Cave M, Alonso-Sanez A, Gonzalez-Lopez KD, et al. A longitudinal study of transmission of tuberculosis in a large prison population. Am J Respir Crit Care Med. 1997;155:719–725. 74. Pelletier AR, DiFerdinando GT Jr, Greenberg AG, Sosin DM, Jones WD Jr, Bloch AB, et al. Tuberculosis in a correctional facility. Arch Intern Med. 1993;153:2692–2695. 75. Weis SE, Miller TL, Hilsenrath PE, Moonan PK. Comprehensive cost description of tuberculosis care. Int J Tuberc Lung Dis. 2005;9(4):467–470. 76. Update: Adverse event data and revised American Thoracic Society/CDC recommendations against the use of rifampin and pyrazinamide for treatment of latent tuberculosis infection. MMWR Morbid Mortal Wkly Rep. 2003;52:735–739.
PURPOSE: Evaluation improves efficiency and effectiveness. Current U.S. tuberculosis (TB) control policies emphasize the treatment of latent TB infection (LTBI). However, this policy, if not targeted, may be inefficient. We determined the efficiency of a state-law mandated TB screening program and a non statelaw mandated one in terms of cost, morbidity, treatment, and disease averted. METHODS: We evaluated two publicly funded metropolitan TB prevention and control programs through retrospective analyses and modeling. Main outcomes measured were TB incidence and prevalence, TB cases averted, and cost. RESULTS: A non state-law mandated TB program for homeless persons in Tarrant County screened 4.5 persons to identify one with LTBI and 82 persons to identify one with TB. A state-law mandated TB program for jail inmates screened 109 persons to identify one with LTBI and 3274 persons to identify one with TB. The number of patients with LTBI treated to prevent one TB case was 12.1 and 15.3 for the homeless and jail inmate TB programs, respectively. Treatment of LTBI by the homeless and jail inmate TB screening programs will avert 11.9 and 7.9 TB cases at a cost of $14,350 and $34,761 per TB case, respectively. CONCLUSIONS: Mandated TB screening programs should be risk-based, not population-based. Non mandated targeted testing for TB in congregate settings for the homeless was more efficient than statelaw mandated targeted testing for TB among jailed inmates. Ann Epidemiol 2006;16:305–312. Ó 2006 Elsevier Inc. All rights reserved. KEY WORDS:
Tuberculosis, Prevention, Public Health, Targeted Testing, Health Economics, Evaluation.
INTRODUCTION Health care in the United States is in crisis (1). Many agree that the current trajectory of health care costs threatens future access to affordable health care. Despite spending a greater proportion of its gross domestic product for health care than other industrialized countries, the US health care system underperforms when measured by important health impacts (e.g., decreased infant mortality or increased life expectancy). Improving the efficiency of health spending, especially ensuring that benefits justify costs, is a key to resolving this crisis. However, strategies to identify the best use of limited resources remain controversial (2). One strategy is to perform cost-effectiveness analysis (CEA) from a societal perspective (3). Systematic use of CEA to determine From the Department of Medicine, University of North Texas Health Science Center at Fort Worth, Fort Worth, TX (T.L.M., P.H., K.L., P.K.M., S.E.W); School of Public Health, Fort Worth, TX (T.L.M., P.H., K.L., P.K.M., S.E.W); Centers for Disease Control and Prevention, Atlanta, GA (S.J.N.M); and Tarrant County Health Department, Fort Worth, TX (S.E.W.). Address correspondence to: Stephen E. Weis, DO, Department of Medicine, University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Blvd, Fort Worth, TX 76107. Tel.: (817) 321-4937; fax: (817) 321-4920. E-mail: [email protected]. Received April 3, 2005; accepted July 5, 2005. Ó 2006 Elsevier Inc. All rights reserved. 360 Park Avenue South, New York, NY 10010
insurance coverage decisions is an elusive goal (4). However, informed decision making does not always require a full CEA. Even in the context of disease elimination, such as tuberculosis (TB) prevention and control in the United States, public health programs should determine practical strategies to provide the most efficient prevention and control impacts. TB remains a public health problem in the United States despite historically low prevalence. In 2004, the United States had 14,511 new reported TB cases, an all-time low (5, 6). This trend caused the Centers for Disease Control and Prevention (CDC) to reevaluate the US TB elimination strategy and recommend targeted testing of specific high-risk populations (Table 1) (7, 8). Identifying and treating persons with latent TB infection (LTBI) is important to this strategy. Additionally, the Institute of Medicine recommended the development of more effective methods for identifying and treating persons with LTBI, but do not provide guidelines on how best to do so (14). Experts generally accept that homeless and jailed persons in the United States are at increased risk for infection with TB (15–25). Many recommendations identify these population groups for TB prevention and control efforts to decrease ongoing TB transmission (21–25). These recommendations target test those most likely to benefit from and comply with treatment recommendations (24, 25). However, mandated 1047-2797/06/$–see front matter doi:10.1016/j.annepidem.2005.07.053
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Selected Abbreviations and Acronyms CEA Z cost-effectiveness analysis TB Z tuberculosis LTBI Z latent tuberculosis infection CDC Z Centers for Disease Control and Prevention TST Z tuberculin skin test TCPHD Z Tarrant County Public Health Department RIF/PZA Z rifampin/pyranazimide
TB targeted testing in specific populations varies across jurisdictions and may not reflect efficient practices. When targeted-testing strategies must be prioritized, their relative cost efficiencies should be considered. In Texas, active TB case-finding is a state-law–mandated program for inmates in jails with population sizes greater than 100 (26). Although this law does not mandate screening for or treatment of LTBI, this intervention does further TB prevention and control goals and is performed routinely in Tarrant County jails (27, 28). However, there are fewer data to guide strategies for TB prevention and control programs in jails than prisons or congregate living facilities for the homeless (19, 21). Nevertheless, TB outbreaks in jails capture public attention and require clearly articulated data-driven strategies (27–36). We compared costs and health impacts between two TB programs in Tarrant County: the correctional health TB surveillance program and a homeless shelter outreach program. We focus on the health impacts of each program designed to identify and treat LTBI. One additional outcome of this study is an economic tool that can be used to evaluate various strategies for TB prevention and control.
METHODS We conducted a retrospective comparison of the cost and health impacts between the Tarrant County, TX, homeless TB screening program and the jail TB screening program. This evaluation was part of the Tuberculosis Epidemiologic Studies Consortium Project, New Model for Assessing
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Tuberculosis Surveillance and Action Performance and Cost, funded by the CDC. The unit of study was the public health program; no individual patient information was used. The study period for the jail program was 335 days from December 19, 2001, through December 18, 2002. Data used for analysis of the homeless program were collected for calendar year 2003. Comparisons are made based on patients with TB diagnosed in the study period and having known treatment duration. Treatment durations reflect all treatment, including that known to occur in other settings. Reports from all TB screening programs in county jail facilities in Tarrant County were included in this evaluation. In Tarrant County, jail inmates are administered a Mantoux tuberculin skin test (TST) with 5 tuberculin unit–strength purified protein derivative. Those with a clearly documented prior positive TST result are not retested. A TST reading of 10 mm or greater induration is defined as a positive result. If there is a history of TB exposure or human immunodeficiency virus infection, positive is defined at 5 mm or greater. All individuals with a newly positive TST result, a previous positive TST result, or symptoms of TB-related illness undergo additional evaluation by medical personnel at the facility. Treatment of LTBI is offered as clinically appropriate. Medically licensed staff directly observed all TB therapy. Jail program data were abstracted from monthly reports compiled by Tarrant County Public Health Department (TCPHD) personnel. These reports included number of evaluations, TST results, radiographs, cultures, diagnosis, and TB risk information (e.g., TST converter, human immunodeficiency virus status, regimen and amount of TB treatment, and final status). We gathered population information from the US Census Bureau (37). The homeless program is an outreach effort by the TCPHD in which homeless persons in a congregate setting are targeted for TB testing. The program includes on-site TB symptom check, chest radiograph, TST, and medical evaluation. TST was performed as described. Area residents had TB exposure, and a positive TST result was defined as 5 mm or greater. TCPHD personnel, who were available
TABLE 1. Comparison of populations at risk for tuberculosis, United States and Tarrant County, Texas, 2002 (6, 7, 9–13) United States Variable Total Homelessa Foreign-born Local jailb a
Population (%) 280,540,330 800,000–3,500,000 (0.3%–1.3%) 32,453,000 (11.6%) 652,082 (0.2%)
No. of cases reported
Tarrant County, Texas Incidence rate (/100,000 population)
Population (%)
No. of cases reported
Incidence rate (/100,000 population)
5.2 110.3–25.2 23.1 Unknown
1,446,219 4,375–8,631 (0.3%–0.6%) 206,061 (14.3%) 3119 (0.2%)
109 13 53 7
7.2 297.1–150.6 26 31c
15,075 883 7659 Unknown
Range is point estimate of the number of homeless at any time in 1 year. Average daily population in 2002. Tuberculosis incidence rate based on number screened.
b c
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for 5 evening hours Monday through Friday, observed treatment on site. Personnel observing TB therapy were experienced in working with homeless persons and successfully completed the CDC core TB training modules, but did not have medical licenses (38). Training included TB symptoms, side effects, directly observed preventive therapy, follow-up, tracking protocols, and safety strategies. In addition, personnel were supervised by public health nurses and physicians. Patients received an incentive for keeping medication appointments, including dietary supplements or fast-food coupons. Resumption of TB therapy for interruptions of less than 3 months did not require reevaluation. No costs accrued to the homeless shelter or patients (39). Costs and activities associated with the detection and treatment of TB in these two settings were estimated as previously described for patients with uncomplicated active TB and LTBI (40). They were adjusted to reflect current conditions and TB treatment recommendations (41–45). Treatment and professional costs were estimated at the midpoint of Medicare’s national average allowance and mean fee for non-Medicare charges, and average wholesale price for drugs was used (40). Costs were adjusted to 2003 US dollars (45). The sums of screening and treatment costs were used for comparison of programs. Costs of negative screening results were adjusted proportionally to the number of LTBI and TB diagnoses made. Estimated hospitalization rates and costs were adjusted to the region (46). We did not consider costs for contact investigations, patient expenses, facilities, administration, or other program costs. Treatment regimens for LTBI were described according to medications used, dosing, and proportion of a full course of treatment completed. We categorized treatment of LTBI as either isoniazid therapy (‘‘long course’’) or other drug combination (‘‘short course’’). Costs and disease risk
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reduction associated with LTBI treatment reflected the duration of treatment (47–57). Therapy was observed, so we assumed ‘‘completer-complier’’ efficacy and cumulative effect for multiple sessions or regimens of LTBI treatment (58). Dosing and duration information were converted to a standard metric reflecting the proportion of recommended treatment for each regimen. We modeled risk reduction from LTBI treatment as a cumulative reduction of disease risk for risk groups from the annual expected risk (47–57). Within the model, recent converters remained at increased risk for 1 year, then their risk decreased to that of remotely infected (47–57). Navigate to http://www.hsc.unt.edu/ intmed/Documents/risk%20reduction%20calculator.xls to access our disease reduction estimation tool. Differences in proportions, medians, and means were calculated. All statistical tests were two sided, with levels of 0.05 or less considered significant. Descriptive statistics were compiled and calculations were performed using Microsoft Excel 2002 (Microsoft Corp., Redmond, WA), SPSS, version 12 (SPSS Inc., Chicago, IL), and STATA 8.0 (StataCorp LP, College Station, TX).
RESULTS During 335 days in 2002, a total of 22,920 jailed inmates underwent state-law–mandated TB screening in the Tarrant County jail system (Table 2). The result of this targeted testing was identification of 14 TB suspects, TB subsequently was diagnosed in seven of these patients, and 211 patients were prescribed treatment for LTBI. A second non– state-law–mandated TB program screened homeless persons in Tarrant County. In this program, 822 homeless persons were screened and 34 TB suspects were identified, TB
TABLE 2. Comparison of the yield of TB infected and diseased patients, by screening program, Tarrant County, Texas, 2002 No. of patients (%)
Screened TST placed Previous positive result Positive TST resultb Treatment for LTBI prescribedc Treated for TB Lost unread No. screened/LTBI No. screened/TB case Screenings/treatmentd
Cost, 2003 (US $)a
per 100,000
Homeless
Jail
p
Homeless
Jail
Homeless
Jail
822 778 (94.7) 63 (7.7) 127 (15.5) 181 (22) 10 (1.2) 245 (29.8) 4.5 82.2 5.7
22,920 21,778 (95) 1142 (5) 303 (2) 211 (0.9) 7 (0.03) 6760 (31.1) 108.7 3274 140
0.179 0.001 !0.001 !0.001 !0.001 0.356 d d d
d d 7664 15,456 22,019 1217 29,817 22,222 1217 d
d d 4983 1322 951 31 29,568 920 31 d
$54,334 d d d $809 $7835 d $300 $5433 $377
$245,244 d d d $774 $7835 d $1163 $35,035 $1498
LTBI, latent tuberculosis infection; TB, tuberculosis; TST, tuberculin skin test. a Cost reflects average cost per treatment, per patient; cost per number screened reflects screening costs required to yield one LTBI or TB diagnosis. Treatment criteria include exposure, symptoms, or other factors not limited to positive screening. b Proportion of tests that were read. c Diagnosis of LTBI may be caused by factors other than positive TST (e.g., exposure, previous positive TST result with inadequate treatment). Number of LTBIs includes 24 homeless program suspects and 7 jail program suspects in whom TB was ruled out. d Number and cost of screenings required to initiate one treatment.
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subsequently was diagnosed in 10 of these patients, and 181 patients were prescribed treatment for LTBI. TB suspects not confirmed as having TB were treated for LTBI. An estimate of the resources required to avert one TB case through screening and treatment of LTBI is a function of the number necessary to screen to detect and treat patients with LTBI and duration of treatment (Table 3). In the homeless program, 69 screenings were required to avert one TB case, 5.7 screenings were needed to initiate one LTBI treatment, and 12.1 treatments were required to avert one case. The jail program found fewer TB cases and required more treatments per TB case averted, resulting in 2142 screenings to avert one TB case. The homeless person TB program cost $14,350 per TB case prevented, and the jail inmate TB program cost $34,761 per TB case prevented. The larger estimated risk reduction achieved by treatment of LTBI in the homeless person TB program will result in 150% more TB averted than will the jail inmate TB program (11.9 versus 7.9 TB cases averted, respectively). LTBI treatments given within the homeless program yielded greater overall levels of completion than the jail program (median homeless program treatment completed Z 0.72 treatment course [midspread Z 0.31 to 1] versus median jail program treatment completed Z 0.26 treatment course [midspread Z 0.06 to 0.89]). Every 12.1 treatments of LTBI initiated in the homeless program and 15.3 treatments
TABLE 3. Outcomes of treatment for LTBI in the homeless and jail screening programs, Tarrant County, Texas, 2002 to 2003 Homeless
Jaila
No. of patients (%)
No. of patients (%)
Treatment for LTBI prescribed 181 Total treated 143 Refused or lost 38 (26.6) Short course 77 (42.5) Long course 66 (36.5) 0.72 (0.31–1) Median treatment completed (midspread)b TB cases preventedc 11.9 Average cost for LTBI treatment 809 (2003 US $)d No. of LTBI treatments 12.1 to prevent 1 TB case Screenings to prevent 1 TB case 69 Screening cost per case preventede ($) 4561 Cost per case preventede ($) 14,350
211 121 47 (22.3) 39 (32.2) 82 (67.8) 0.26 (0.06–0.89) 7.9 774 15.3 2,142 22,919 34,761
TB, tuberculosis; LTBI, latent tuberculosis infection. a Excludes those with unknown treatment durations (w20%). b Median of recommended therapy, short and long course combined in full course equivalents. c From risk reduction during 20 years. d Cost for average proportion completed adjusted to reflect treatment regimen. e Total cost to detect and treat sufficient LTBI to prevent one case and excludes 43 cases with duration unknown in jail cohort.
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initiated in the jail program resulted in a sufficient risk reduction to prevent one patient from developing TB. Estimated individual screening and treatment costs were slightly greater in the homeless population, largely because of the use of a chest radiograph added to the TST for every patient at the initial screening. The cost per patient diagnosed was much greater in the jail program than the homeless program (TB Z $35,035 versus $5433 and LTBI Z $1163 versus $300, respectively). There were no differences in outcomes or estimated treatment costs for patients with TB in the jail and homeless programs. In both, standard treatment regimens were prescribed, and all completed therapy. We predict that LTBI treatment in the homeless population achieved 74% of the current maximum possible disease reduction, considering its risk groups (Table 4). The jail inmate population achieved 52% of the maximum possible disease reduction. When LTBI incidence is decreased by 50% and 75% in sensitivity analyses, we estimate minimum costs per active case averted range from $21,082 to $71,514 if all treatment is completed and $28,943 to $137,306 with treatment completed as found. Within the jail, 6760 persons did not have their TST read because of release. Our findings suggest that had a test been available to more rapidly diagnose TB, and additional two TB cases and 62 latent or suspected TB infections would have been discovered. A similar proportion of TSTs were not read among homeless persons. We predict that another three TB cases and 56 latent or suspected TB infections would have been discovered if all TSTs were read.
DISCUSSION Using data routinely accessible by local health agencies, we found that a homeless TB screening program was more than 21 times more effective in identifying LTBI and almost 40 times more effective in detecting TB than a state-law–mandated jail TB screening program. The homeless program averted more cases of TB at less cost. These results show that mandated TB screening should be justified on population risk. Determining population risk does not require extensive research, but often can be done by using sampling or preexisting data. Risk-based TB screening programs that include congregate living facilities for homeless persons should be highly effective in averting TB disease. Both targeted screening programs detected much greater morbidity than if unrestricted broad-population screening were used. In addition, our data provide validation to guidelines recommending targeted testing for TB.
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TABLE 4. Sensitivity analysis showing benefits and cost per TB case averted when the diagnosis of LTBI is made, Tarrant County, Texas, 2002 to 2003 LTBI diagnosis made Homeless, n Z 143 Jail, n Z 121 Homeless, n Z 72 Jail, n Z 61 Homeless, n Z 36 Jail, n Z 30
Maximum benefita
Actual benefitb
When LTBI is as found 16.2 11.9 15.2 7.9 When LTBI is decreased 50% 8.1 5.9 7.6 4 When LTBI is decreased 75% 3.9 3 3.8 2
LTBI incidence (/100,000 population)
Cost per TB case avertedc (2003 US $)
2202 92
With maximum benefit 10,541 18,067
Actual 14,350 34,761
1101 46
21,082 36,133
28,943 68,653
551 23
43,786 71,514
56,922 137,306
Total actual cost (2003 US $)d 170,765 274,613
LTBI, latent tuberculosis infection; TB, tuberculosis. a In cases averted over time where risk factors remain constant, maximum benefit implies 100% compliance with recommended treatment. b Actual benefit implies benefit with treatment completion rates as found. Screened persons: 828 homeless screened, 22,920 jail screened. c Cost to detect and treat sufficient LTBI to avert one case. Costs represent screening and treatment for LTBI and TB suspects only. d Excludes cost for 43 inmates with treatment duration unknown.
The growth in the cost of US health care is not sustainable. There is growing recognition that greater efficiency in the health sector will involve tough decisions about priorities, with resource allocation going to the most efficient activities (1–4). These decisions are difficult to make for diseases for which the goal is elimination (14). Decreasing TB infection in the general population makes traditional case-finding increasingly expensive at the margin, requiring new approaches (8, 17, 19–24). Modeling has been used to attempt to identify the best TB control practices (52, 56, 57). We combined these techniques with program data to compare for the first time the relative effectiveness of two TB programs. Homelessness predisposes people with LTBI to progress to TB, and TB in this population has been identified as a major source of morbidity in metropolitan areas across the United States (59–64). Studies of TB isolates from homeless persons detected unsuspected TB transmission across jurisdictional borders and between homeless and nonhomeless persons and found transmission of multidrug-resistant TB (62, 65). Estimates of the national homeless population in the late 1990s varied from 800,000 to 3,500,000 persons (66). Assuming TB morbidity similar to that found in the Tarrant County homeless program, the national homeless population may represent a reservoir of 22,019 patients with LTBI per 100,000 screened. Per 100,000 similar screenings and LTBI treatments, we estimate an investment of $20,806,148 in detection and treatment would identify 1217 persons with TB in the screening year and avert 1449 cases. Likewise, 100,000 jail inmates screened would result in identification of 31 TB cases and avert 47 cases at a cost of $1,633,767. The ultimate cost or savings from such efforts will require study of the full cost of TB, but our findings indicate that achieving the goal of national TB elimination will require innovative programs in homeless and other high-risk populations.
An insight from a study of strategies for TB risk reduction was that access to care is more important to reducing TB and deaths in the homeless than improving effectiveness of therapy (19). The TCPHD homeless program is designed to be maximally accessible. This may contribute to the high acceptance and completion of treatment for LTBI in that program. Seventy-nine percent of homeless patients started LTBI therapy, and the median proportion of LTBI therapy completed was 72%. In a study of 4 years of LTBI treatment in homeless persons in Denver, only 21% with LTBI were started on therapy and only 28% of those completed therapy (69). In an LTBI treatment adherence study, homeless persons randomly assigned to usual care in San Francisco received a median of 2 months of isoniazid therapy, with similar results found in other studies (67–70). An unexpected finding in our study is that the Tarrant County homeless population was more stable in terms of successful therapy than the jail population. Using monitoring and evaluation to measure cost and performance in TB control programs has been described previously (71). That analysis identified wasted resources and missed opportunities for TB control within a county jail system (71). Our study describes how monitoring and evaluation can suggest more efficient use of resources among many choices for public health action. At midyear 2003, there were 691,301 jailed inmates held nationally, and that number is increasing (72). Turnover is high, with jail inmates usually confined a year or less (72). Although there are few data on results of TB screening in jails, there is evidence of TB transmission within jails and from jails into the community (15, 16, 27–35, 72–74). It was suggested that TB testing of jail inmates has a major role in reducing TB in the community (30). In the Tarrant County jail program, we found a TB prevalence of 31 cases per 100,000 and an LTBI prevalence of 921 cases per
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100,000. This emphasizes the importance of the jail as a reservoir of TB and a location where targeted testing and treatment of TB can occur, but inmate turnover and treatment follow-up challenges remain. We recognize that we do not include all costs associated with TB, including those generated by contact investigations, secondary transmission, and patient costs (50, 51, 58, 75). All such costs are assumed to be similar in this study. We therefore underestimated the complete cost of a TB case by failing to consider these additional costs and hence underestimated the full savings from averting a case of TB (50, 75). Some differences exist between the jail inmate and homeless person cohorts that may affect comparability. Existing programmatic data were collected, allowing only gross demographic comparisons of the groups. The study periods were not concurrent. During the time the jail program was analyzed, rifampin/pyranazimide (RIF/PZA) therapy was not known to carry undue risk and was recommended as appropriate for short-duration LTBI therapy (76). During the period the homeless program was analyzed, RIF/PZA therapy rarely was used because of potential side effects. However, these differences do not affect our conclusions because the RIF/PZA combination therapy has been shown to increase treatment completion compared with isoniazid therapy. Lack of complete information on dosing resulted in approximately 20% of jail LTBI treatments being excluded from analysis; however, these missing data were random, with no indication that this information would change our findings. TB screening is recommended in many situations by guidelines and mandated in some by legal statute (15–26). Decisions about populations required to undergo TB screenings are made at a political level for many reasons. The protection of public health and protection of prisoners from exposure to potentially fatal preventable illnesses often must be considered before questions of efficiency. Wide variations in TB risks and public health infrastructures make it difficult to generalize the experience in Tarrant County to the United States, and both inmate and homeless populations offer challenges for TB control that have been well described (8, 9, 14–21, 24, 27–36). Finding relative efficiency in the homeless program in Tarrant County does not require that jail programs be abandoned for homeless programs. Rather, our findings suggest that strategies for TB elimination should ensure efficient use of resources within communities through an evaluation component. We illustrate how monitoring and evaluation can help set priorities to maximize return on spending for TB interventions. By directing prevention and control programs toward reservoirs of latent disease and populations for which risk makes them effective and efficient screening targets, we can improve our progress toward achieving TB elimination in the United States.
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The authors gratefully acknowledge the contributions to this work made by Karen Kardaras, Maureen Wilce, and Bridget Young.
REFERENCES 1. Walker DM. Health Care System Crisis: Growing Challenges Point to Need for Fundamental Reform. Government Accountability Office. Available at: http://www.gao.gov/cghome/hccrisis/. Accessed November 20, 2004. 2. Gillick MR. Medicare coverage for technological innovations-time for new criteria? N Engl J Med. 2004;350:2199–2203. 3. Russell LB, Gold MR, Siegel JE, Daniels N, Weinstein MC. The role of cost-effectiveness analysis in health and medicine. JAMA. 1996;276: 1172–1177. 4. Tunis SR. Why Medicare has not established criteria for coverage decisions. N Engl J Med. 2004;350:2196–2198. 5. Centers for Disease Control and Prevention. Reported Tuberculosis in the United States, 2003. Atlanta, GA: CDC; 2004. 6. Centers for Disease Control and Prevention. Fact Sheet: Tuberculosis in the United States, 2004. Available at: http://www.cdc.gov/od/oc/media/ pressrel/fs050317.htm. Accessed June 22, 2005. 7. Centers for Disease Control and Prevention. Tuberculosis morbidity among U.S.-born and foreign-born populationsd2000. MMWR Morbid Mortal Wkly Rep. 2002;51:101–104. 8. Centers for Disease Control and Prevention. Tuberculosis elimination revisited: Obstacles, opportunities, and a renewed commitment. MMWR Morbid Mortal Wkly Rep. 1999;48:No. RR–9:1–13. 9. Martin K. Tarrant County Community Development Division, personal communication. December 14, 2004. 10. 2000 US Census American Community Survey, 2002. Available at: www.census.gov. Accessed February 1, 2004. 11. Henry J. Kaiser Foundation. 2400 Sand Hill Road, Menlo Park, CA. Long-Term Care: Medicaid’s Role and Challenges. Publication no. 2172. Henry J. Kaiser Foundation; 1999. 12. US Department of Justice, Office of Justice Programs. Prison and Jail Inmates at Midyear, 2002. Bureau of Justice Statistics Bulletin, April 2003. Available at: http://www.ojp.usdoj.gov/bjs/pub/pdf/pjim02.pdf. Accessed January 11, 2005. 13. US Census Bureau. Foreign-Born Population of the United States Current Population SurveydMarch 2002 Detailed Tables (PPL-162). Available at: www.census.gov/prod/2003pubs/p20-539.pdf. Accessed February 26, 2004. 14. Institute of Medicine. Ending Neglect: The Elimination of Tuberculosis in the United States. Washington, DC: National Academy; 2000. 15. Wilcock K, Hammett TM, Widom R, Epstein J. Tuberculosis in Correctional Facilities, 1994–1995. National Institute of Justice Research in Brief, US Department of Justice, Office of Justice Programs; US Department of Justice, Washington, DC 1996. 16. Hammett TM, Harmon P, Maruschak LM. 1996–1997 Update: HIV/ AIDS, STDs, and TB in Correctional Facilities. US Department of Justice, Office of Justice Programs; US Department of Justice, Washington, DC 1999. 17. Brewer TF, Heymann SJ, Krumplitsch SM, Wilson ME, Colditz GA, Fineberg HV. Strategies to decrease tuberculosis in US homeless populations: A computer simulation model. JAMA. 2001;286:834–842. 18. Moonan PK, Bayona M, Quitugua TN, Oppong J, Dunbar D, Jost Jr KC, et al. Using GIS technology to identify areas of tuberculosis transmission and incidence. Int J Health Geographics. 2004;3:23–33. 19. Rendleman NJ. Mandated tuberculosis screening in a community of homeless people. Am J Prev Med. 1999;17:108–113. 20. Centers for Disease Control and Prevention. Prevention and Control of Tuberculosis in Correctional Facilities. Atlanta, GA: CDC; 1995.
AEP Vol. 16, No. 4 April 2006: 305–312
21. Centers for Disease Control and Prevention. Screening for tuberculosis and tuberculosis infection in high risk populations: Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1994;44:19–34. 22. Horsburgh CR Jr. Priorities for the treatment of latent tuberculosis infection in the United States. N Engl J Med. 2004;350:2060–2067. 23. Centers for Disease Control and Prevention. Targeted tuberculin testing and treatment of latent tuberculosis infection. MMWR Morbid Mortal Wkly Rep. 2000;49(No. RR-6):1–54. 24. Centers for Disease Control and prevention. Prevention and control of tuberculosis in US communities with at-risk minority populations: Recommendations of the Advisory Council for the Elimination of Tuberculosis and Prevention and control of tuberculosis among homeless persons: Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1992;41(RR-5):1–11. 25. Essential components of a tuberculosis prevention and control program. Recommendations of the Advisory Council for the Elimination of Tuberculosis. MMWR Morbid Mortal Wkly Rep. 1995;44:1–16. 26. Texas Health and Safety Code, Title 25, Part I, Chapter 97, Sub-Chapter H. Available at: http://info.sos.state.tx.us/pls/pub/readtac$ext.ViewTAC? tac_view Z 5&ti Z 25&pt Z 1&ch Z 97&sch Z H&rl Z Y. Accessed December 1, 2004. 27. King L, Geis G. Tuberculosis transmission in a large urban jail. JAMA. 1977;237:791–792. 28. Jones TF, Schaffner W. Miniature chest radiograph screening for tuberculosis in jails: A cost-effectiveness analysis. Am J Respir Crit Care Med. 2001;164:77–81. 29. Lobato MN, Roberts CA, Bazerman LB, Hammett TM. Public health and correctional collaboration in tuberculosis control. Am J Prev Med. 2004; 27:112–117. 30. Hammett TM, Harmon MP, Rhodes W. The burden of infectious disease among inmates of and releasees from US correctional facilities, 1997. Am J Public Health. 2002;92:1789–1794. 31. White MC, Tulsky JP, Portillo CJ, Menendez E, Cruz E, Goldenson J. Tuberculosis prevalence in an urban jail: 1994 and 1998. Int J Tuberc Lung Dis. 2001;5:400–404.
Miller et al. FINDING EFFICIENCY AMONG TB CONTROL STRATEGIES
311
41. US Department of Labor. Bureau of Labor Statistics Occupational Employment Statistics, May 2003. Available at: http://www.bls.gov/oes/2003/may/ oes211091.htm#nat. Accessed November 22, 2004. 42. US Department of Labor. Bureau of Labor Statistics. Consumer Price Index Urban Wage Earners and Clerical Workers, Medical Care US City Average. Available at: http://data.bls.gov/cgi-bin/surveymost. Accessed November 22, 2004. 43. Centers for Disease Control and Prevention. Treatment of tuberculosis. MMWR Morbid Mortal Wkly Rep. 2003;52:1–88. 44. US Department of Labor. Bureau of Labor Statistics. CPI Urban Wage Earners and Clerical Workers, Medical Care Services US City Average. Available at: http://data.bls.gov/cgi-bin/surveymost. Accessed November 22, 2004. 45. US Department of Labor, Bureau of Labor Statistics. CPI for Medical Care Commodities. Available at: http://www.bls.gov/news.release/cpi.t05.htm. Accessed November 22, 2004. 46. Taylor Z, Marks SM, Rios Burrows NM, Weis SE, Stricof RL, Miller B. Causes and costs of hospitalization of tuberculosis patients in the United States. Int J Tuberc Lung Dis. 2000;4:931–939. 47. Gordin F, Chaisson RE, Matts JP, Miller C, de Lourdes Garcia M, Hafner R, et al. Rifampin and pyrazinimide vs. isoniazid for prevention of tuberculosis in HIV-infected persons: An international randomized trial. JAMA. 2000;283:1445–1450. 48. IUAT Committee on Prophylaxis. Efficacy of various durations of isoniazid preventive therapy for tuberculosis: Five years of follow-up in the IUAT trial. Bull World Health Org. 1982;60(44):555–564. 49. Ferebee SHE. Controlled chemoprophylaxis trials in tuberculosis: A general review. Adv Tuberc Res. 1970;17:28–106. 50. Comstock GW. How much isoniazid is needed for prevention of tuberculosis among immunocompetent adults? Int J Tuberc Lung Dis. 1999; 10:847–850. 51. Javitz HS, Ward M. Value of antimicrobials in the prevention and treatment of tuberculosis in the United States. Int J Tuberc Lung Dis. 2002;6:275–288. 52. Taylor Z. The cost-effectiveness of screening for latent tuberculosis infection. Int J Tuberc Lung Dis. 2000;4(suppl):S127–133.
32. Tulsky JP, White MC, Dawson C, Hoynes TM, Goldenson J, Schecter G. Screening for tuberculosis in jail and clinic follow-up after release. Am J Public Health. 1998;88:223–226.
53. Salpeter EE, Salpeter SR. A mathematical model for the epidemiology of tuberculosis, with estimates of the reproductive number and infectiondelay function. Am J Epidemiol. 1998;47:398–406.
33. White MC, Tulsky JP, Reilly P, MacIntosh HW, Hoynes TM, Goldenson J. A clinical trial of financial incentive to go to the tuberculosis clinic for isoniazid preventive therapy for released jail inmates. Int J Tuberc Lung Dis. 1998;2:506–512.
54. Snyder DC, Paz AE, Moehle-Boetani JC, Fallstad R, Black RL, Chin DP. Tuberculosis prevention in methadone maintenance clinics: Effectiveness and cost-effectiveness. Am J Respir Crit Care Med. 1999;160: 178–185.
34. Lincoln T, Brannan GL, Lynch V, Conklin TJ, Clancey T, Rose TN, et al. Completing tuberculosis prophylaxis in jail: Targeting treatment and comparison of rifampin/pyrazinamide with isoniazid regimens. Int J Tuberc Lung Dis. 2004;8:306–311.
55. Snyder DC, Chin D. Cost-effectiveness analysis of directly observed therapy for patients with tuberculosis at low risk for treatment default. Am J Respir Crit Care Med. 1999;160:582–586.
35. Reichman LB. On target. A tuberculosis control strategy whose time has come. Ann Intern Med. 1999;131:617–618. 36. Jones TF, Craig AS, Valway SE, Woodley CL, Schaffner W. Transmission of tuberculosis in jails. Ann Intern Med. 1999;131:557–563. 37. US Census Bureau. US Census, 2000. Available at: http://quickfacts. census.gov/qfd/states/48/48439.html. Accessed February 1, 2004. 38. Centers for Disease Control and Prevention. Self Study Modules on Tuberculosis 1-5, Course #SS3035. National Center for HIV, STD, and TB Prevention, Division of Tuberculosis Elimination. Available at: http:// www.phppo.cdc.gov/PHTN/tbmodules/Default.htm. Accessed December 20, 2004. 39. Moonan PK, Bayona M, Quitugua TN, Oppong J, Burgess G, Hines NL, et al. Targeted Screening for Tuberculosis Combining GIS and Genotyping Technology. Presented at American Public Health Association Annual Meeting, San Francisco, CA, November 15, 2003. 40. Qualls N. Centers for Disease control and prevention, personal communication. December 14, 2004.
56. Salpeter SR, Sanders GD, Salpeter EE, Owens DK. Monitored isoniazid prophylaxis for low-risk tuberculin reactors older than 35 years of age: A risk-benefit and cost-effectiveness analysis. Ann Intern Med. 1997;127:1051–1061. 57. Rose DN. Benefits of screening for latent Mycobacterium tuberculosis infection. Arch Intern Med. 2000;160:1513–1521. 58. Floyd K. Costs and effectivenessdThe impact of economic studies on TB control. Tuberculosis 2003;83:187–200. 59. Rendleman NJ. Mandated tuberculosis screening in a community of homeless people. Am J Prev Med. 1999;17:108–113. 60. Barnes PF, Yang Z, Pogoda JM, Preston-Martin S, Jones BE, Otaya M, et al. Foci of tuberculosis transmission in central Los Angeles. Am J Respir Crit Care Med. 1999;159:1081–1086. 61. Lathan M, Ntaate Musaka L, Hooper N, Golub J, Baruch N, Mucahy D, et al. Cross-jurisdictional transmission of Mycobacterium tuberculosis in Maryland and Washington, DC, 1996-2000, linked to the homeless. Emerg Infect Dis. 2002;8:1249–1251.
312
Miller et al. FINDING EFFICIENCY AMONG TB CONTROL STRATEGIES
62. Munsiff S, Bassoff T, Nivin B, Li H, Sharma A, Bifani P, et al. Molecular epidemiology of multidrug-resistant tuberculosis, New York City, 19951997. Emerg Infect Dis. 2002;8:1230–1238. 63. Centers for Disease Control and Prevention. Public health dispatch: Tuberculosis outbreak among homeless personsdKing County, Washington, 2002-2003. MMWR Morbid Mortal Wkly Rep. 2003;52: 1209–1210. 64. Bock NN, Metzger BS, Tapia JR, Blumberg HM. A tuberculin screening and isoniazid preventive therapy program in an inner-city population. Am J Respir Crit Care Med. 1999;159:295–300. 65. French AL, Welbel SF, Dietrich SE, Mosher LB, Breall PS, Paul WS, et al. Use of DNA fingerprinting to assess tuberculosis infection control. Ann Intern Med. 1998;129:856–861. 66. Burt ML. What Will It Take to End Homelessness? Urban Institute. 2001. Available at: http://www.urban.org/url.cfm?ID Z 310305. Accessed December 1, 2004. 67. Kong PM, Tapy J, Calixto P, et al. Skin-test screening and tuberculosis transmission among the homeless. Emerg Infect Dis. 2002;8: 1280–1284. 68. Tulsky JP, Pilote L, Hahn JA, Zolopa AJ, Burke M, Chesney M, et al. Adherence to isoniazid prophylaxis in the homeless: A randomized controlled trial. Arch Intern Med. 2000;160:697–702. 69. Burman WJ, Cohn DL, Rietmeijer CA, Judson FN, Sbarbaro JA, Reves RR. Noncompliance with directly-observed therapy for tuberculosis:
AEP Vol. 16, No. 4 April 2006: 305–312
Epidemiology and effect on the outcome of treatment. Chest. 1997; 111:1168–1173. 70. Pablos-Me´ndez A, Knirsch CA, Barr RG, Lerner BH, Frieden TR. Nonadherence in tuberculosis treatment: Predictors and consequences in New York City. Am J Med. 1997;102:164–170. 71. McNabb SJN, Surdo A, Redmond A, Cobb J, Wiley J, Chakrabarti S, et al. Applying a new conceptual framework to evaluate public health surveillance and action, Hillsborough County, Florida, 2002. Ann Epidemiol. 2004;14:640–645. 72. US Department of Justice, Office of Justice Programs. Bureau of Justice Statistics Profile of Jail Inmates, 2002. Available at: www.ojp.usdoj.gov/ bjs/. Accessed December 12, 2004. 73. Chaves F, Dronda MD, Cave M, Alonso-Sanez A, Gonzalez-Lopez KD, et al. A longitudinal study of transmission of tuberculosis in a large prison population. Am J Respir Crit Care Med. 1997;155:719–725. 74. Pelletier AR, DiFerdinando GT Jr, Greenberg AG, Sosin DM, Jones WD Jr, Bloch AB, et al. Tuberculosis in a correctional facility. Arch Intern Med. 1993;153:2692–2695. 75. Weis SE, Miller TL, Hilsenrath PE, Moonan PK. Comprehensive cost description of tuberculosis care. Int J Tuberc Lung Dis. 2005;9(4):467–470. 76. Update: Adverse event data and revised American Thoracic Society/CDC recommendations against the use of rifampin and pyrazinamide for treatment of latent tuberculosis infection. MMWR Morbid Mortal Wkly Rep. 2003;52:735–739.