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A Clinical Outcomes and Cost Analysis Comparing Photoselective Vaporization of the Prostate to Alternative Minimally Invasive Therapies and Transurethral Prostate Resection for the Treatment of Benign Prostatic Hyperplasia
A Clinical Outcomes and Cost Analysis Comparing Photoselective Vaporization of the Prostate to Alternative Minimally Invasive Therapies and Transurethral Prostate Resection for the Treatment of Benign Prostatic Hyperplasia Mark D. Stovsky,*,† Robert I. Griffiths† and Steven B. Duff† From the Department of Urology, Case School of Medicine, University Hospitals of Cleveland (MDS), Cleveland, Ohio, Department of Medicine, Johns Hopkins University School of Medicine (RIG), Baltimore, Maryland, Health Economics Consulting (RIG), Craftsbury, Vermont, and Veritas Health Economics Consulting (SBD), Carlsbad, California
Purpose: We critically evaluated the clinical outcomes and cost characteristics of alternative procedural treatment options for symptomatic benign prostatic hyperplasia. Materials and Methods: An outcomes and cost analysis was performed for benign prostatic hyperplasia treatments, including photoselective vaporization, microwave thermotherapy, transurethral needle ablation, interstitial laser coagulation and transurethral resection. Clinical outcomes were measured by the percent improvement in American Urological Association/International Prostate Symptom Score, the maximum uroflowmetry rate and quality of life score. An economic simulation model was constructed to estimate the expected cost of benign prostatic hyperplasia procedural therapies from a payer perspective. The model included costs of initial treatment, followup care, adverse events and re-treatment. Sensitivity and threshold analyses tested the impact of changing model inputs on base case results. Results: Ablative therapies showed better improvement in symptom score, flow rate and quality of life score compared to thermotherapy procedures. Photoselective vaporization resulted in the largest beneficial changes in American Urological Association/International Prostate Symptom Score, the maximum uroflowmetry rate and the quality of life score at all time points evaluated, followed by transurethral resection and then interstitial laser coagulation. The estimated cost was lower for photoselective vaporization than for any other procedural option at any interval studied. Sensitivity analyses indicated that the results of baseline analyses were robust to reasonable changes in clinical and economic inputs to the model. Conclusions: Compared to alternative treatment options photoselective vaporization of the prostate is a clinically efficacious and cost-effective treatment for symptomatic benign prostatic hyperplasia. Key Words: prostate, prostatic hyperplasia, costs and cost analysis, outcome assessment (health care)
enign prostatic hyperplasia is a major cause of urinary tract symptoms in men. The choice among management alternatives for BPH is a complex process. Many competing treatment options that demonstrate different clinical outcomes, economic costs and reimbursement characteristics coexist in the market. When lower urinary tract symptoms are mild and there is no absolute indication for therapy, ie urinary retention, recurrent urinary infections, refractory hematuria or renal insufficiency, BPH may be managed expectantly. If symptoms worsen, BPH may be treated with pharmacological, surgical or minimally invasive procedural options. Traditionally the mainstays of BPH treatment have been medical (␣-adrenergic blockers and 5␣-reductase inhibitors) or surgical (TURP, TUIP and open simple prostatectomy). Recently peer reviewed data were published, evaluating medications as monotherapy or in combination for BPH.1–3
B
Submitted for publication July 20, 2005. * Correspondence and requests for reprints: University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, Ohio, 44106 (telephone: 216-844-3009; FAX: 216-844-1900; e-mail: gowildgo@aol. com). † Financial interest and/or other relationship with Laserscope.
0022-5347/06/1764-1500/0 THE JOURNAL OF UROLOGY® Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION
New procedural options have been introduced that attempt to produce clinically acceptable results in terms of objective and subjective measures of treatment outcome, while at the same time limiting the risk of adverse perioperative and postoperative events. To date there have been few published reviews comparing emerging procedural treatments with traditional interventions such as transurethral resection for BPH in terms of clinical efficacy or the total cost of care. We comparatively examined clinical outcomes measures and developed an economic model to estimate the payer cost of alternative commonly used procedural options for BPH, including initial treatment, followup care, re-treatment and the management of adverse events. MATERIALS AND METHODS Framing the Economic Analysis In this analysis we developed a decision-analytic Markov model using TreeAge Pro™ to estimate the costs and evaluate the clinical outcomes of 5 alternative procedural interventions for BPH, including PVP, ILC, TURP, TUNA and TUMT (see figure). TUMT was further stratified according to AUA Clinical Guidelines for the Management of BPH4
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Vol. 176, 1500-1506, October 2006 Printed in U.S.A. DOI:10.1016/j.juro.2006.06.064
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
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Simplified schematic of clinical economic model. Branches emanating from procedure 1 arm are duplicated on procedure 2 arm ([⫹]). After treatment option is chosen, patients enter Markov tree, representing health states in which patients may exist during each 1-month cycle. Patients are alive or dead. If alive, patients may experience adverse event related to procedure. Each terminal branch (triangles) ends in health state to which patients return to begin next monthly cycle. Patients remain in model for 24 cycles (2 years) or until death. M, Markov node, indicating entry into Markov tree. Square nodes represent decision to use specific procedure for BPH. Circles represent chance nodes.
into Prostatron® Version 2.0, Prostatron® Version 2.5 and Targis®, such that 7 interventions were included in the analysis. The patient population in this analysis was assumed to have lower urinary tract symptoms indicative of BPH and require procedural management with one of the interventions indicated. In the model patients were followed for 2 years following the initial intervention. Costs of the initial intervention, routine followup care related to BPH, the management of intervention related adverse events and procedural re-treatment were included in the model. Economic analysis included costs directly associated with procedural intervention. The cost of pharmacological therapy was not included in the current model. The model was used to project total expected costs related to these procedural interventions during 2 years from the perspective of Medicare as well as their clinical outcomes, consisting of AUASS/I-PSS, QMAX and QOL, during the same time horizon. Parameter Estimates Costs of initial procedures. Direct medical costs included in the model were calculated from the perspective of Medicare in 2005 (tables 1 and 2). The total cost of each procedural intervention for BPH was obtained by identifying physician and facility payments from the 2005 Medicare fee schedules and then summing these payments. Medicare payments for BPH procedures depend on the setting in which the procedure is performed, that is hospital outpatient, hospital inpatient, physician office or ambulatory surgery center. For purposes of this analysis we assumed that all PVP procedures were performed in a hospital outpatient setting, all TUNA and TUMT procedures were performed at a physician office site of service and all TURP procedures were performed in a hospital inpatient setting. We assumed that 86% of ILC procedures were performed at a physician
office site of service, 9% were performed at a freestanding ambulatory surgery center and the remaining 5% were performed in a hospital outpatient setting (Ethicon, personal communication, November 21, 2005). Facility payments were identified using the Ambulatory Payment Classification code for hospital outpatient procedures (PVP and 5% of ILC), the Ambulatory Surgery Center code for surgery center procedures (9% of ILC) and the diagnostic related group code for hospital inpatient procedures (TURP).5– 8 Physician payments were identified using CPT codes5– 8 and these payments were adjusted depending on the setting of care in which the procedure was performed. In addition to urologist payment, anesthesiologist payment was assumed for all procedures performed outside of a physician office. Costs of adverse events. Costs of adverse events related to the procedural interventions, of followup care related to BPH and of re-treatment were obtained from an analysis of Medicare claims data. Using the Medicare 5% institutional and physician/supplier files from 1999 to 2001, representing public use Medicare data available at the time that our study was performed, we identified physician/supplier claims with an ICD-9-CM code of 600.xx, indicating a diagnosis of BPH, plus 1 of 4 CPT codes indicating a procedure for BPH, that is 52601 TURP, 52647 ILC or PVP, 53850 TUMT or 53852 TUNA. These patients were considered to have undergone a procedure for BPH. For each patient we constructed a history of medical services for up to 1 year following the date of the procedure. We called this the observation period. To identify the Medicare costs of managing adverse events related to surgery we identified all ICD-9-CM diagnosis codes from the Medicare claims of each patient with a procedure for BPH during the observation period. These codes were then labeled with a text description and output to
TABLE 1. Costs and probabilities included in model % TUMT Adverse Event
Event Cost (2005 $)
% PVP
% ILC
% TURP
% TUNA
Prostatron® Version 2.0
Prostatron® Version 2.5
Targis®
Incontinence Urinary tract infection Impotence/erectile dysfunction Dysuria/irritative voiding Bladder neck stenosis/stricture Urinary retention Hematuria Reoperation
286 314 282 183 534 294 313 3,889
3 5 0 9 3 6 5 1
3 19 1 33 0 12 15 10
3 6 10 15 7 5 6 5
1 17 3 31 3 20 4 23
2 9 3 28 1 23 2 10
No data 9 1 74 2 15 No data 10
6 9 No data No data 3 6 No data 16
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OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT TABLE 2. Procedure and followup costs Initial Procedure (2005 $)
PVP ILC TURP TUNA TUMT
2,852 3,129* 3,748 3,765 3,948
Followup care was $22 per month in 2005 dollars. * Weighted average cost of $3,129 was used in base case analyses based on the distribution of ILC procedures performed in the 3 settings, including physician office in 86%, hospital outpatient department in 9% and freestanding ambulatory surgery center in 5%, and procedure cost in those settings, including $3,222, $2,807 and $2,090, respectively.
an Excel™ spreadsheet. Based on the text descriptions we identified diagnosis codes indicating services related to each of 7 adverse events, including 1) dysuria/irritative voiding, 2) urinary retention, 3) hematuria, 4) bladder neck stenosis/ stricture, 5) incontinence, 6) urinary tract infection and 7) impotence/erectile dysfunction. These adverse events were included in the model based on clinical relevance, as determined from the AUA BPH guideline data set4 and the peer reviewed literature on PVP and ILC,9 –33 and their anticipated economic importance. We then searched all institutional and physician/supplier claims of each patient undergoing a procedure for BPH during the observation period to identify services with an ICD9-CM code indicating 1 of the 7 adverse events. We summed the total cost of these services by type of adverse event and type of surgical procedure during 1 year to calculate the total Medicare paid amount associated with managing each type of adverse event. To avoid introducing bias into the model associated with random variation in the costs of adverse events for different procedures we calculated the weighted average cost of each adverse event across all procedures. These adverse event costs were then incorporated into the model. All costs were inflated to 2005 dollars using the Medical Care Component of the Consumer Price Index.34 Costs of re-treatment. From the cohort of Medicare patients identified as having undergone procedural therapy for BPH we identified those with 1 or more additional procedures during the observation period. They were identified using the same algorithm as in the initial procedure except the ICD-9-CM diagnosis code for BPH did not also have to be present in the physician/supplier claim containing the CPT code for 1 procedure. To build up the total cost of re-treatment we identified inpatient and outpatient institutional claims with dates of service overlapping those for the physician/supplier claim containing the procedure code. Medicare paid amount(s) for the overlapping institutional claim(s) was then added to the paid amount for the physician/supplier claim to calculate the total re-treatment procedure cost to Medicare. TURP procedures were included only if they had an institutional and a physician/supplier claim, and they were excluded if the hospital stay for inpatient admission exceeded 30 days. As a final step, we calculated a weighted average cost per re-treatment across all types of initial procedures. This cost was incorporated into the model. Costs of routine followup care. We calculated the monthly Medicare paid amounts associated with followup
care related to BPH during the observation period. We identified all institutional and physician/supplier claims with an ICD-9-CM code of 600.xx but without an adverse event code, indicating that the service was related to BPH but not directly related to managing a complication of surgery. We then calculated the weighted average Medicare paid amount per patient month for followup care across the different procedures. Probability of adverse events. The probability of adverse events associated with TURP, TUNA and TUMT was obtained from the AUA Clinical Guidelines for the Management of BPH (table 1).4 PVP and ILC are not included in the guidelines because there were few published studies at the time that the guidelines were developed. Therefore, to ensure a study data source derived from a common methodology we performed a literature search, review, data extraction and meta-analysis of PVP and ILC clinical trials9 –33 based on the approach described in the AUA guidelines methodology4 to determine the probability of adverse events for these 2 modalities. According to the guidelines we calculated an average probability of each adverse event associated with PVP and ILC, as weighted by study sample size.9 –33 Clinical outcomes scores. An approach similar to that described was applied to obtain clinical outcomes scores for the model, consisting of AUASS/I-PSS, QMAX and QOL. Changes in clinical outcomes scores or rates of change from baseline to 6, 12 and 24 months for TURP, TUNA and TUMT were obtained from the BPH guidelines data set.4 Comparable data on PVP and ILC were obtained from a review and meta-analysis of the PVP and ILC literature9 –33 based on the AUA guidelines methodology.4 In the model reported change scores were applied to calculated baseline values of 22 for AUASS/I-PSS, 8.5 for QMAX and 4.5 for QOL to calculate the raw outcomes score for each measure on a monthly basis. Baseline values in the model were assumed to be identical across the procedural interventions. This approach was used to normalize the interventions at baseline.
Analysis In the analysis hypothetical cohorts of 10,000 patients enter each surgical intervention arm of the model 1 at a time. Each patient is followed on a monthly basis for 2 years. In month 1 the patient incurs the cost of the procedural intervention. Each month the patient is exposed to the risk of adverse events related to the intervention and to the risk of requiring re-treatment. Event probabilities were converted into monthly hazards, such that the cumulative hazard in the model after 1 year equaled the weighted average event probability calculated from the BPH guidelines (TURP/ TUNA/TUMT) and PVP/ILC data. In the model each adverse event can occur only once per patient during the simulation. However, when it occurs, the patient incurs the annualized cost of that event, as calculated from the Medicare claims analysis. Similarly re-treatment can occur only once per patient during the simulation. For each patient the model adds together the costs of the initial intervention, monthly followup care, adverse events and re-treatment when they occur, and calculates a total cost per patient
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
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TABLE 3. Clinical outcomes % Decrease From Baseline (av/mo) Time Horizon AUASS/I-PSS: 6 Mos 12 Mos 24 Mos QMAX: 6 Mos 12 Mos 24 Mos QOL: 6 Mos 12 Mos 24 Mos
PVP
ILC
TURP
TUNA
Prostatron® 2.0 TUMT
Prostatron® 2.5 TUMT
Targis® TUMT
73 (5.92) 74 (5.80) 76 (5.25)
64 (7.83) 63 (8.16) 62 (8.38)
67 (7.35) 67 (7.30) 66 (7.58)
52 (10.5) 49 (11.2) 44 (12.3)
20 (17.5) 35 (14.3) 40 (13.2)
17 (18.3) 30 (15.3) 39 (13.3)
46 (11.9) 45 (12.1) 46 (12.0)
188 (24.5) 199 (25.4) 221 (27.3)
102 (17.2) 97 (16.8) 89 (16.1)
124 (19) 125 (19.1) 117 (18.5)
35 (11.5) 40 (11.9) 28 (10.9)
17 (9.92) 26 (10.8) 28 (10.9)
22 (10.4) 37 (11.7) 45 (12.3)
31 (11.2) 40 (11.9) 45 (12.3)
81 (0.84) 82 (0.82) 83 (0.75)
53 (2.12) 54 (2.07) 55 (2.00)
76 (1.06) 76 (1.09) 73 (1.21)
68 (1.44) 66 (1.54) 61 (1.74)
18 (3.68) 30 (3.16) 34 (2.97)
11 (3.98) 21 (3.53) 24 (3.43)
49 (2.30) 50 (2.23) 52 (2.18)
AUASS/IPSS and QOL are inversely related to improvement in symptoms and quality of life and, therefore, decrease in AUASS/IPSS and QOL indicates fewer symptoms and better quality of life, respectively.
during 2 years. The model then calculates the average cost per patient across the 10,000 patients in each cohort. In each month of simulation the model multiplies the monthly change scores for AUASS/I-PSS, QMAX and QOL to baseline scores to calculate the patient raw scores during that month. Raw scores are then added during 24 months. The model calculates the average score per patient per month and the average score per patient-month in each cohort of 10,000 patients. In addition to base-case analyses done best cost and probability inputs to the model, we also performed sensitivity analyses to assess the extent to which our results and conclusions changed when key parameter estimates and assumptions were varied over plausible ranges. For example, we varied the costs of each BPH procedure to reflect changes in Medicare reimbursement that occurred in 2006, adverse event rates associated with PVP, our assumptions about the site of service for ILC and the time horizon during which adverse events occur. In addition, we performed threshold analysis to determine the PVP re-treatment rate at which the expected cost of PVP and TURP would be equal. RESULTS Base Case Analyses Table 3 shows the expected percent change from baseline in the 3 clinical outcomes scores after 6, 12 and 24 months as well as the average clinical score per month during these intervals. As shown, in each procedural intervention arm of the model most beneficial changes from baseline occurred during the first 6 months of simulation with only small beneficial or detrimental changes thereafter. Notable exceptions were Prostatron® 2.0 and 2.5, for which scores continued to improve considerably during the entire period. PVP resulted in the largest beneficial changes in all clinical outcomes measured at all time points evaluated, followed by TURP and then ILC. TUNA showed greater improvements (decreases) in QOL scores than ILC but not compared to TURP or PVP. The largest difference between PVP and TURP was observed for QMAX. Table 4 lists cost findings. Results indicate that most costs were consumed during the first 6 months, which is to be expected given the cost of the interventions relative to adverse events and re-treatment. Most costs at all time periods were due to the initial procedural intervention. Ad-
verse events related to the intervention comprised approximately 6% to 30% of the total cost depending on the intervention and time point considered. The expected cost per patient at all 3 time points was lowest for PVP, followed by ILC and then TURP. Larger cost increases between 6 and 24 months were observed for ILC and TUNA than for the other therapies, showing the importance of re-treatment costs during this interval. Sensitivity Analyses To assess the robustness of the results a number of different parameters were varied over plausible ranges. 1) Because ILC is performed in multiple settings, we examined whether the results and conclusions would change if ILC were assumed to be performed only in the least costly (ambulatory surgery center) or most costly (physician office) setting of care. When only performed in a physician office setting, ILC remained more costly than PVP ($4,819 vs $3,589 at 24 months) but less costly than all other treatment modalities. However, when we assumed that ILC was only performed at the ambulatory surgery center, ILC became the least costly treatment modality at 12 months ($2,916) but was more costly than PVP by 24 months ($3,653 vs $3,589). 2) Since the clinical outcomes of PVP and TURP were most similar, we performed sensitivity analysis to determine the PVP re-treatment rate at which the cost of PVP would be equal to that of TURP. We found that the PVP re-treatment rate needed to be approximately 17% for PVP and TURP to be cost equivalent. 3) We varied the adverse event rates derived from PVP data and found that even with rates set at the maximum observed values the expected PVP cost at 12 and 24 months was still less than that of all other treatment
TABLE 4. Expected cost per patient Time Horizon ($)
PVP ILC TURP TUNA TUMT: Prostatron® Version 2.0 Prostatron® Version 2.5 Targis®
6 Mos
12 Mos
24 Mos
3,020 3,573 4,030 4,457
3,214 3,965 4,331 5,089
3,589 4,754 4,927 6,179
4,348 4,402 4,414
4,753 4,817 4,859
5,461 5,488 5,699
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OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
modalities. 4) When initial treatment cost was adjusted to reflect the Medicare 2006 reimbursement schedule, the overall cost of PVP remained lower than that of the other procedural treatment options. In this final sensitivity analysis the cost of ILC remained less than that of TURP, while that of TUNA and TUMT were higher than that of TURP. TUNA showed the highest expected cost at the 12 and 24-month intervals. DISCUSSION The selection of an appropriate treatment strategy for symptomatic BPH can be challenging. Ideally the choice among competing therapeutic alternatives should be made with primary concern for clinical efficacy, patient specific goals, and a reasonable assessment of the risks and cost of treatment. For the procedural management of BPH myriad competing options exist with different clinical outcomes, cost and reimbursement characteristics. Pharmacological therapy remains the initial treatment choice for most urologists and patients. While gold standard treatments such as TURP, TUIP and open simple prostatectomy are still performed, market forces have hastened the development of less invasive procedural alternatives, including the demand by urologists for procedural therapies that are easy to learn and provide durable improvements in objective outcomes parameters. Similarly patients desire therapies that provide reasonable clinical efficacy, while limiting the risk of untoward events that historically have made the gold standard treatments comparatively less attractive.35 While current reimbursement methodologies largely discount clinical outcomes and downstream costs, payers are beginning to scrutinize the cost/benefit characteristics of treatment decisions in the context of the emerging pay for performance system. Given the widely held assumption that less invasive procedural options provide acceptable clinical efficacy at substantially decreased risk, they have largely supplanted TURP, TUIP and open simple prostatectomy in the treatment selection process. Few groups have critically evaluated this assumption or the cost-effectiveness of alternative BPH procedural therapies. We have developed a model that meshes traditional objective and subjective measures of the technical success of therapy with a rigorous appraisal of the total cost of care. The model incorporates a data source based on a common methodology derived from a meta-analytic review of the peer reviewed literature for minimally invasive BPH procedural therapy. The calculation of treatment cost, reflecting initial and downstream clinical events, represents a unique economic parameter, which in conjunction with a comparative assessment of clinical outcomes data allows more complete assessment of the cost/benefit characteristics of various procedural BPH therapies. When evaluating clinical outcomes data, we found that ablative BPH treatments, that is procedures designed to remove a large volume of obstructive transition zone tissue, including PVP and TURP, produced more substantive improvement in objective and subjective parameters than thermotherapy, such as ILC, TUNA and TUMT. PVP showed the greatest improvements in AUASS/I-PSS, QMAX and QOL across all intervals. ILC was superior to TUNA and TUMT with respect to AUASS/I-PSS and QMAX. However, TUNA
showed a small QOL advantage over ILC at each interval. In general TUMT produced the least substantive improvements in the outcomes parameters studied. Of the procedural therapies studied PVP was less costly than TURP, ILC, TUNA and TUMT. The cost savings of this procedure stemmed from the rates of adverse events and re-treatment, which on a comparative basis were lower for PVP. Sensitivity analysis revealed several notable findings. Analysis with respect to ILC demonstrated the importance of examining how sites of service can impact the payer cost of BPH procedural therapy. Since ILC is currently typically performed at the physician office site of service, the total cost of this procedure remained higher than that of PVP but lower than that of the other minimally invasive options at all intervals. Also, sensitivity analysis to assess the impact of changes in PVP re-treatment relative to TURP showed that the PVP re-treatment rate required for these procedures to be cost equivalent was more then 3 times greater than the highest re-treatment rate reported in the PVP literature.14 From this we conclude that differences in the expected cost of PVP and TURP are robust to reasonable changes in the rate of PVP re-treatment. Sensitivity analysis to investigate variations in adverse event rates and changes in Medicare reimbursement on total procedural cost produced similar demonstrations of the economic efficiency of PVP. The complexity of the analysis yielded several challenges. While only published peer reviewed material from the AUA guidelines, PVP and ILC literature was abstracted and analyzed using a common general methodology, this type of review did not allow true standardization of data across studies due to certain factors, including the use of prospective and retrospective data, differences in patient cohort demographics, variation in the degree of voiding dysfunction across study populations and discordance in patient co-morbid medical conditions. However, the common methodology ensured consistency in our treatment of adverse event rates and clinical outcomes data for all procedural BPH therapies studied. When considering the economic analysis, our use of Medicare claims file data produced a unique look at adverse event, followup care and re-treatment costs that reflected actual services provided to patients. The result was an unbiased view of the true downstream costs associated with each BPH procedural treatment option. However, we were limited by a lack of contemporaneous Medicare claims file data because information available for public access generally lags real time by several years. As more up to date claims file data become available, model outputs should reflect this new information. Our analysis of Medicare claims file data also necessarily depended on the accuracy of physician and facility reporting/billing practices. However, current reimbursement policies and fee schedules for Medicare and private payers are based on similar nationally reported information. We believe that our use of claims file data represents an accurate and comprehensive means of calculating the total payer costs of the procedural therapies studied. CONCLUSIONS Because physicians and patients are forced to choose from among BPH therapies with widely differing clinical out-
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT comes, cost and reimbursement characteristics, tools that add clarity to the treatment selection process are invaluable. Our study using an innovative model to compare procedural treatment options for BPH from outcomes and economic cost perspectives shows that, in comparison to alternative minimally invasive options and TURP, PVP is a clinically efficacious and cost-effective treatment for symptomatic BPH.
10.
11.
12.
Abbreviations and Acronyms AUASS ⫽ American Urological Association symptom score BPH ⫽ benign prostatic hyperplasia CPT ⫽ Physicians’ Current Procedural Terminology ICD-9-CM ⫽ International Classification of Diseases, 9th revision, clinical modification ILC ⫽ interstitial laser coagulation of the prostate I-PSS ⫽ International Prostate Symptom Score PVP ⫽ photoselective vaporization of the prostate QMAX ⫽ maximum uroflowmetry rate QOL ⫽ quality of life score TUMT ⫽ transurethral microwave thermotherapy of the prostate TUNA ⫽ transurethral radio frequency needle ablation of the prostate TURP ⫽ transurethral prostate resection
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Bachmann, A., Schürch, L., Ruszat, R., Wyler, S. F., Seifert, H. H., Müller, A. et al: Photoselective vaporization (PVP) versus transurethral resection of the prostate (TURP): a prospective bi-centre study of perioperative morbidity and early functional outcome. Eur Urol, 48: 965, 2005 Carter, A., Sells, H. and O’Boyle, P. J.: High-power KTP laser for the treatment of symptomatic benign prostatic enlargement. BJU Int, 83: 857, 1999 Hai, M. A. and Malek, R. S.: Photoselective vaporization of the prostate: initial experience with a new 80 W KTP laser for the treatment of benign prostatic hyperplasia. J Endourol, 17: 93, 2003 Malek, R. S., Kuntzman, R. S. and Barrett, D. M.: Photoselective potassium-titanyl-phosphate laser vaporization of the benign obstructive prostate: observations on long-term outcomes. J Urol, 174: 1344, 2005 Miki, T., Kojima, T., Nonomura, N., Matsumiya, K., Kokado, Y., Yoshioka, T. et al: Transurethral visual laser ablation of the prostate for benign prostatic hyperplasia using a KTP/ YAG laser. Int J Urol, 4: 576, 1997 Reich, O., Bachmann, A., Siebels, M., Hofstetter, A., Stief, C. G. and Sulser, T.: High power (80 W) potassium-titanylphosphate laser vaporization of the prostate in 66 high risk patients. J Urol, 173: 158, 2005 Sulser, T., Reich, O., Wyler, S., Ruszat, R., Casella, R., Hofstetter, A. et al: Photoselective KTP laser vaporization of the prostate: first experiences with 65 procedures. J Endourol, 18: 976, 2004 Te, A. E., Malloy, T. R., Stein, B. S., Ulchaker, J. C., Nseyo, U. O., Hai, M. A. et al: Photoselective vaporization of the prostate for the treatment of benign prostatic hyperplasia: 12-month results from the first United States multicenter prospective trial. J Urol, 172: 1404, 2004 Costello, A., Agarwal, D., Crowe, H. and Lynch, W.: Evaluation of interstitial diode laser therapy for treatment of benign prostatic hyperplasia. Tech Urol, 5: 202, 1999 Daehlin, L. and Hedlund, H.: Interstitial laser coagulation in patients with lower urinary tract symptoms from benign prostatic obstruction: treatment under sedoanalgesia with pressure-flow evaluation. BJU Int, 84: 628, 1999 De la Rosette, J., Muschter, R., Lopez, M. and Gillatt, D.: Interstitial laser coagulation in the treatment of benign prostatic hyperplasia using a diode-laser system with temperature feedback. Br J Urol, 80: 433, 1997 Diana, M., Schettini, M. and Gallucci, M.: Minimally invasive treatment of BPH with interstitial diode laser coagulation. Arch Ital Urol Androl, 71: 1, 1999 Floratos, D., Sonke, G., Francisca, E., Kiemeney, L., Debruyne, F. and de la Rosette, J.: Long-term follow-up of laser treatment for lower urinary tract symptoms suggestive of bladder outlet obstruction. Urology, 56: 604, 2000 Greenberger, M. and Steiner, M.: The University of Tennessee experience with the Indigo 830e laser device for the minimally invasive treatment of benign prostatic hyperplasia: interim analysis. World J Urol, 16: 386, 1998 Kochakarn, W., Nilsakulwat, S., Roongruangsilp, U. and Muangman, V.: Interstitial laser coagulation for the treatment of benign prostatic hyperplasia: a 3 year follow-up of 30 cases. J Med Assoc Thai, 84: 1126, 2001 Kursh, E., Concepcion, R., Chan, S., Hudson, P., Ratner, M. and Eyre, R.: Interstitial laser coagulation versus transurethral prostate resection for treating benign prostatic obstruction: a randomized trial with 2-year follow-up. Urology, 61: 573, 2003 Liedberg, F., Adell, L., Hagberg, G. and Palmqvist, I.: Interstitial laser coagulation versus transurethral resection of the prostate for benign prostatic hyperplasia. Scand J Urol Nephrol, 37: 494, 2003
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Martenson, A. and de la Rosette, J.: Interstitial laser coagulation in the treatment of benign prostatic hyperplasia using a diode laser system: results of an evolving technology. Prostate Cancer Prostatic Dis, 2: 148, 1999 28. Muschter, R., de la Rosette, J., Whitfield, H., Pellerin, J., Madersbacher, S. and Gillatt, D.: Initial human clinical experience with diode laser interstitial treatment of benign prostatic hyperplasia. Urology, 48: 223, 1996 29. Nishizawa, K., Kobayashi, T., Watanabe, J. and Ogura, K.: Interstitial laser coagulation of the prostate for management of acute urinary retention. J Urol, 170: 879, 2003 30. Nishizawa, K., Kobayashi, T., Mitsumori, K., Watanabe, J. and Ogura, K.: Intermittent catheterization time required after interstitial laser coagulation of the prostate. Urology, 64: 79, 2004 31. Polepalle, S. and Monga, M.: Interstitial laser therapy for benign prostatic hyperplasia in the anticoagulated patient. Tech Urol, 7: 285, 2001
32.
Tsui, K., Chang, P., Chang, S. and Cheng, H.: Interstitial laser photocoagulation for treatment of benign prostatic hypertrophy: outcomes and cost effectiveness. Chang Gung Med J, 26: 799, 2003 33. Williams, J.: Interstitial laser coagulation of the prostate: introduction of a volume-based treatment formula with 12month follow-up. World J Urol, 16: 392, 1998 34. Consumer Price Index: Medical Care Component. United States Department of Labor, Bureau of Labor Statistics. Available at http://data.bls.gov/cgi-bin/dsrv. Accessed November 2005 35. Mebust, W. K., Holtgrewe, H. L., Cockett, A. T. K., Peters, P. C. and Writing Committee: Transurethral prostatectomy: immediate and postoperative complications—a cooperative study of 143 participating institutions evaluating 3,885 patients. J Urol, 141: 243, 1989
Purpose: We critically evaluated the clinical outcomes and cost characteristics of alternative procedural treatment options for symptomatic benign prostatic hyperplasia. Materials and Methods: An outcomes and cost analysis was performed for benign prostatic hyperplasia treatments, including photoselective vaporization, microwave thermotherapy, transurethral needle ablation, interstitial laser coagulation and transurethral resection. Clinical outcomes were measured by the percent improvement in American Urological Association/International Prostate Symptom Score, the maximum uroflowmetry rate and quality of life score. An economic simulation model was constructed to estimate the expected cost of benign prostatic hyperplasia procedural therapies from a payer perspective. The model included costs of initial treatment, followup care, adverse events and re-treatment. Sensitivity and threshold analyses tested the impact of changing model inputs on base case results. Results: Ablative therapies showed better improvement in symptom score, flow rate and quality of life score compared to thermotherapy procedures. Photoselective vaporization resulted in the largest beneficial changes in American Urological Association/International Prostate Symptom Score, the maximum uroflowmetry rate and the quality of life score at all time points evaluated, followed by transurethral resection and then interstitial laser coagulation. The estimated cost was lower for photoselective vaporization than for any other procedural option at any interval studied. Sensitivity analyses indicated that the results of baseline analyses were robust to reasonable changes in clinical and economic inputs to the model. Conclusions: Compared to alternative treatment options photoselective vaporization of the prostate is a clinically efficacious and cost-effective treatment for symptomatic benign prostatic hyperplasia. Key Words: prostate, prostatic hyperplasia, costs and cost analysis, outcome assessment (health care)
enign prostatic hyperplasia is a major cause of urinary tract symptoms in men. The choice among management alternatives for BPH is a complex process. Many competing treatment options that demonstrate different clinical outcomes, economic costs and reimbursement characteristics coexist in the market. When lower urinary tract symptoms are mild and there is no absolute indication for therapy, ie urinary retention, recurrent urinary infections, refractory hematuria or renal insufficiency, BPH may be managed expectantly. If symptoms worsen, BPH may be treated with pharmacological, surgical or minimally invasive procedural options. Traditionally the mainstays of BPH treatment have been medical (␣-adrenergic blockers and 5␣-reductase inhibitors) or surgical (TURP, TUIP and open simple prostatectomy). Recently peer reviewed data were published, evaluating medications as monotherapy or in combination for BPH.1–3
B
Submitted for publication July 20, 2005. * Correspondence and requests for reprints: University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, Ohio, 44106 (telephone: 216-844-3009; FAX: 216-844-1900; e-mail: gowildgo@aol. com). † Financial interest and/or other relationship with Laserscope.
0022-5347/06/1764-1500/0 THE JOURNAL OF UROLOGY® Copyright © 2006 by AMERICAN UROLOGICAL ASSOCIATION
New procedural options have been introduced that attempt to produce clinically acceptable results in terms of objective and subjective measures of treatment outcome, while at the same time limiting the risk of adverse perioperative and postoperative events. To date there have been few published reviews comparing emerging procedural treatments with traditional interventions such as transurethral resection for BPH in terms of clinical efficacy or the total cost of care. We comparatively examined clinical outcomes measures and developed an economic model to estimate the payer cost of alternative commonly used procedural options for BPH, including initial treatment, followup care, re-treatment and the management of adverse events. MATERIALS AND METHODS Framing the Economic Analysis In this analysis we developed a decision-analytic Markov model using TreeAge Pro™ to estimate the costs and evaluate the clinical outcomes of 5 alternative procedural interventions for BPH, including PVP, ILC, TURP, TUNA and TUMT (see figure). TUMT was further stratified according to AUA Clinical Guidelines for the Management of BPH4
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Vol. 176, 1500-1506, October 2006 Printed in U.S.A. DOI:10.1016/j.juro.2006.06.064
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
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Simplified schematic of clinical economic model. Branches emanating from procedure 1 arm are duplicated on procedure 2 arm ([⫹]). After treatment option is chosen, patients enter Markov tree, representing health states in which patients may exist during each 1-month cycle. Patients are alive or dead. If alive, patients may experience adverse event related to procedure. Each terminal branch (triangles) ends in health state to which patients return to begin next monthly cycle. Patients remain in model for 24 cycles (2 years) or until death. M, Markov node, indicating entry into Markov tree. Square nodes represent decision to use specific procedure for BPH. Circles represent chance nodes.
into Prostatron® Version 2.0, Prostatron® Version 2.5 and Targis®, such that 7 interventions were included in the analysis. The patient population in this analysis was assumed to have lower urinary tract symptoms indicative of BPH and require procedural management with one of the interventions indicated. In the model patients were followed for 2 years following the initial intervention. Costs of the initial intervention, routine followup care related to BPH, the management of intervention related adverse events and procedural re-treatment were included in the model. Economic analysis included costs directly associated with procedural intervention. The cost of pharmacological therapy was not included in the current model. The model was used to project total expected costs related to these procedural interventions during 2 years from the perspective of Medicare as well as their clinical outcomes, consisting of AUASS/I-PSS, QMAX and QOL, during the same time horizon. Parameter Estimates Costs of initial procedures. Direct medical costs included in the model were calculated from the perspective of Medicare in 2005 (tables 1 and 2). The total cost of each procedural intervention for BPH was obtained by identifying physician and facility payments from the 2005 Medicare fee schedules and then summing these payments. Medicare payments for BPH procedures depend on the setting in which the procedure is performed, that is hospital outpatient, hospital inpatient, physician office or ambulatory surgery center. For purposes of this analysis we assumed that all PVP procedures were performed in a hospital outpatient setting, all TUNA and TUMT procedures were performed at a physician office site of service and all TURP procedures were performed in a hospital inpatient setting. We assumed that 86% of ILC procedures were performed at a physician
office site of service, 9% were performed at a freestanding ambulatory surgery center and the remaining 5% were performed in a hospital outpatient setting (Ethicon, personal communication, November 21, 2005). Facility payments were identified using the Ambulatory Payment Classification code for hospital outpatient procedures (PVP and 5% of ILC), the Ambulatory Surgery Center code for surgery center procedures (9% of ILC) and the diagnostic related group code for hospital inpatient procedures (TURP).5– 8 Physician payments were identified using CPT codes5– 8 and these payments were adjusted depending on the setting of care in which the procedure was performed. In addition to urologist payment, anesthesiologist payment was assumed for all procedures performed outside of a physician office. Costs of adverse events. Costs of adverse events related to the procedural interventions, of followup care related to BPH and of re-treatment were obtained from an analysis of Medicare claims data. Using the Medicare 5% institutional and physician/supplier files from 1999 to 2001, representing public use Medicare data available at the time that our study was performed, we identified physician/supplier claims with an ICD-9-CM code of 600.xx, indicating a diagnosis of BPH, plus 1 of 4 CPT codes indicating a procedure for BPH, that is 52601 TURP, 52647 ILC or PVP, 53850 TUMT or 53852 TUNA. These patients were considered to have undergone a procedure for BPH. For each patient we constructed a history of medical services for up to 1 year following the date of the procedure. We called this the observation period. To identify the Medicare costs of managing adverse events related to surgery we identified all ICD-9-CM diagnosis codes from the Medicare claims of each patient with a procedure for BPH during the observation period. These codes were then labeled with a text description and output to
TABLE 1. Costs and probabilities included in model % TUMT Adverse Event
Event Cost (2005 $)
% PVP
% ILC
% TURP
% TUNA
Prostatron® Version 2.0
Prostatron® Version 2.5
Targis®
Incontinence Urinary tract infection Impotence/erectile dysfunction Dysuria/irritative voiding Bladder neck stenosis/stricture Urinary retention Hematuria Reoperation
286 314 282 183 534 294 313 3,889
3 5 0 9 3 6 5 1
3 19 1 33 0 12 15 10
3 6 10 15 7 5 6 5
1 17 3 31 3 20 4 23
2 9 3 28 1 23 2 10
No data 9 1 74 2 15 No data 10
6 9 No data No data 3 6 No data 16
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OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT TABLE 2. Procedure and followup costs Initial Procedure (2005 $)
PVP ILC TURP TUNA TUMT
2,852 3,129* 3,748 3,765 3,948
Followup care was $22 per month in 2005 dollars. * Weighted average cost of $3,129 was used in base case analyses based on the distribution of ILC procedures performed in the 3 settings, including physician office in 86%, hospital outpatient department in 9% and freestanding ambulatory surgery center in 5%, and procedure cost in those settings, including $3,222, $2,807 and $2,090, respectively.
an Excel™ spreadsheet. Based on the text descriptions we identified diagnosis codes indicating services related to each of 7 adverse events, including 1) dysuria/irritative voiding, 2) urinary retention, 3) hematuria, 4) bladder neck stenosis/ stricture, 5) incontinence, 6) urinary tract infection and 7) impotence/erectile dysfunction. These adverse events were included in the model based on clinical relevance, as determined from the AUA BPH guideline data set4 and the peer reviewed literature on PVP and ILC,9 –33 and their anticipated economic importance. We then searched all institutional and physician/supplier claims of each patient undergoing a procedure for BPH during the observation period to identify services with an ICD9-CM code indicating 1 of the 7 adverse events. We summed the total cost of these services by type of adverse event and type of surgical procedure during 1 year to calculate the total Medicare paid amount associated with managing each type of adverse event. To avoid introducing bias into the model associated with random variation in the costs of adverse events for different procedures we calculated the weighted average cost of each adverse event across all procedures. These adverse event costs were then incorporated into the model. All costs were inflated to 2005 dollars using the Medical Care Component of the Consumer Price Index.34 Costs of re-treatment. From the cohort of Medicare patients identified as having undergone procedural therapy for BPH we identified those with 1 or more additional procedures during the observation period. They were identified using the same algorithm as in the initial procedure except the ICD-9-CM diagnosis code for BPH did not also have to be present in the physician/supplier claim containing the CPT code for 1 procedure. To build up the total cost of re-treatment we identified inpatient and outpatient institutional claims with dates of service overlapping those for the physician/supplier claim containing the procedure code. Medicare paid amount(s) for the overlapping institutional claim(s) was then added to the paid amount for the physician/supplier claim to calculate the total re-treatment procedure cost to Medicare. TURP procedures were included only if they had an institutional and a physician/supplier claim, and they were excluded if the hospital stay for inpatient admission exceeded 30 days. As a final step, we calculated a weighted average cost per re-treatment across all types of initial procedures. This cost was incorporated into the model. Costs of routine followup care. We calculated the monthly Medicare paid amounts associated with followup
care related to BPH during the observation period. We identified all institutional and physician/supplier claims with an ICD-9-CM code of 600.xx but without an adverse event code, indicating that the service was related to BPH but not directly related to managing a complication of surgery. We then calculated the weighted average Medicare paid amount per patient month for followup care across the different procedures. Probability of adverse events. The probability of adverse events associated with TURP, TUNA and TUMT was obtained from the AUA Clinical Guidelines for the Management of BPH (table 1).4 PVP and ILC are not included in the guidelines because there were few published studies at the time that the guidelines were developed. Therefore, to ensure a study data source derived from a common methodology we performed a literature search, review, data extraction and meta-analysis of PVP and ILC clinical trials9 –33 based on the approach described in the AUA guidelines methodology4 to determine the probability of adverse events for these 2 modalities. According to the guidelines we calculated an average probability of each adverse event associated with PVP and ILC, as weighted by study sample size.9 –33 Clinical outcomes scores. An approach similar to that described was applied to obtain clinical outcomes scores for the model, consisting of AUASS/I-PSS, QMAX and QOL. Changes in clinical outcomes scores or rates of change from baseline to 6, 12 and 24 months for TURP, TUNA and TUMT were obtained from the BPH guidelines data set.4 Comparable data on PVP and ILC were obtained from a review and meta-analysis of the PVP and ILC literature9 –33 based on the AUA guidelines methodology.4 In the model reported change scores were applied to calculated baseline values of 22 for AUASS/I-PSS, 8.5 for QMAX and 4.5 for QOL to calculate the raw outcomes score for each measure on a monthly basis. Baseline values in the model were assumed to be identical across the procedural interventions. This approach was used to normalize the interventions at baseline.
Analysis In the analysis hypothetical cohorts of 10,000 patients enter each surgical intervention arm of the model 1 at a time. Each patient is followed on a monthly basis for 2 years. In month 1 the patient incurs the cost of the procedural intervention. Each month the patient is exposed to the risk of adverse events related to the intervention and to the risk of requiring re-treatment. Event probabilities were converted into monthly hazards, such that the cumulative hazard in the model after 1 year equaled the weighted average event probability calculated from the BPH guidelines (TURP/ TUNA/TUMT) and PVP/ILC data. In the model each adverse event can occur only once per patient during the simulation. However, when it occurs, the patient incurs the annualized cost of that event, as calculated from the Medicare claims analysis. Similarly re-treatment can occur only once per patient during the simulation. For each patient the model adds together the costs of the initial intervention, monthly followup care, adverse events and re-treatment when they occur, and calculates a total cost per patient
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
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TABLE 3. Clinical outcomes % Decrease From Baseline (av/mo) Time Horizon AUASS/I-PSS: 6 Mos 12 Mos 24 Mos QMAX: 6 Mos 12 Mos 24 Mos QOL: 6 Mos 12 Mos 24 Mos
PVP
ILC
TURP
TUNA
Prostatron® 2.0 TUMT
Prostatron® 2.5 TUMT
Targis® TUMT
73 (5.92) 74 (5.80) 76 (5.25)
64 (7.83) 63 (8.16) 62 (8.38)
67 (7.35) 67 (7.30) 66 (7.58)
52 (10.5) 49 (11.2) 44 (12.3)
20 (17.5) 35 (14.3) 40 (13.2)
17 (18.3) 30 (15.3) 39 (13.3)
46 (11.9) 45 (12.1) 46 (12.0)
188 (24.5) 199 (25.4) 221 (27.3)
102 (17.2) 97 (16.8) 89 (16.1)
124 (19) 125 (19.1) 117 (18.5)
35 (11.5) 40 (11.9) 28 (10.9)
17 (9.92) 26 (10.8) 28 (10.9)
22 (10.4) 37 (11.7) 45 (12.3)
31 (11.2) 40 (11.9) 45 (12.3)
81 (0.84) 82 (0.82) 83 (0.75)
53 (2.12) 54 (2.07) 55 (2.00)
76 (1.06) 76 (1.09) 73 (1.21)
68 (1.44) 66 (1.54) 61 (1.74)
18 (3.68) 30 (3.16) 34 (2.97)
11 (3.98) 21 (3.53) 24 (3.43)
49 (2.30) 50 (2.23) 52 (2.18)
AUASS/IPSS and QOL are inversely related to improvement in symptoms and quality of life and, therefore, decrease in AUASS/IPSS and QOL indicates fewer symptoms and better quality of life, respectively.
during 2 years. The model then calculates the average cost per patient across the 10,000 patients in each cohort. In each month of simulation the model multiplies the monthly change scores for AUASS/I-PSS, QMAX and QOL to baseline scores to calculate the patient raw scores during that month. Raw scores are then added during 24 months. The model calculates the average score per patient per month and the average score per patient-month in each cohort of 10,000 patients. In addition to base-case analyses done best cost and probability inputs to the model, we also performed sensitivity analyses to assess the extent to which our results and conclusions changed when key parameter estimates and assumptions were varied over plausible ranges. For example, we varied the costs of each BPH procedure to reflect changes in Medicare reimbursement that occurred in 2006, adverse event rates associated with PVP, our assumptions about the site of service for ILC and the time horizon during which adverse events occur. In addition, we performed threshold analysis to determine the PVP re-treatment rate at which the expected cost of PVP and TURP would be equal. RESULTS Base Case Analyses Table 3 shows the expected percent change from baseline in the 3 clinical outcomes scores after 6, 12 and 24 months as well as the average clinical score per month during these intervals. As shown, in each procedural intervention arm of the model most beneficial changes from baseline occurred during the first 6 months of simulation with only small beneficial or detrimental changes thereafter. Notable exceptions were Prostatron® 2.0 and 2.5, for which scores continued to improve considerably during the entire period. PVP resulted in the largest beneficial changes in all clinical outcomes measured at all time points evaluated, followed by TURP and then ILC. TUNA showed greater improvements (decreases) in QOL scores than ILC but not compared to TURP or PVP. The largest difference between PVP and TURP was observed for QMAX. Table 4 lists cost findings. Results indicate that most costs were consumed during the first 6 months, which is to be expected given the cost of the interventions relative to adverse events and re-treatment. Most costs at all time periods were due to the initial procedural intervention. Ad-
verse events related to the intervention comprised approximately 6% to 30% of the total cost depending on the intervention and time point considered. The expected cost per patient at all 3 time points was lowest for PVP, followed by ILC and then TURP. Larger cost increases between 6 and 24 months were observed for ILC and TUNA than for the other therapies, showing the importance of re-treatment costs during this interval. Sensitivity Analyses To assess the robustness of the results a number of different parameters were varied over plausible ranges. 1) Because ILC is performed in multiple settings, we examined whether the results and conclusions would change if ILC were assumed to be performed only in the least costly (ambulatory surgery center) or most costly (physician office) setting of care. When only performed in a physician office setting, ILC remained more costly than PVP ($4,819 vs $3,589 at 24 months) but less costly than all other treatment modalities. However, when we assumed that ILC was only performed at the ambulatory surgery center, ILC became the least costly treatment modality at 12 months ($2,916) but was more costly than PVP by 24 months ($3,653 vs $3,589). 2) Since the clinical outcomes of PVP and TURP were most similar, we performed sensitivity analysis to determine the PVP re-treatment rate at which the cost of PVP would be equal to that of TURP. We found that the PVP re-treatment rate needed to be approximately 17% for PVP and TURP to be cost equivalent. 3) We varied the adverse event rates derived from PVP data and found that even with rates set at the maximum observed values the expected PVP cost at 12 and 24 months was still less than that of all other treatment
TABLE 4. Expected cost per patient Time Horizon ($)
PVP ILC TURP TUNA TUMT: Prostatron® Version 2.0 Prostatron® Version 2.5 Targis®
6 Mos
12 Mos
24 Mos
3,020 3,573 4,030 4,457
3,214 3,965 4,331 5,089
3,589 4,754 4,927 6,179
4,348 4,402 4,414
4,753 4,817 4,859
5,461 5,488 5,699
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OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT
modalities. 4) When initial treatment cost was adjusted to reflect the Medicare 2006 reimbursement schedule, the overall cost of PVP remained lower than that of the other procedural treatment options. In this final sensitivity analysis the cost of ILC remained less than that of TURP, while that of TUNA and TUMT were higher than that of TURP. TUNA showed the highest expected cost at the 12 and 24-month intervals. DISCUSSION The selection of an appropriate treatment strategy for symptomatic BPH can be challenging. Ideally the choice among competing therapeutic alternatives should be made with primary concern for clinical efficacy, patient specific goals, and a reasonable assessment of the risks and cost of treatment. For the procedural management of BPH myriad competing options exist with different clinical outcomes, cost and reimbursement characteristics. Pharmacological therapy remains the initial treatment choice for most urologists and patients. While gold standard treatments such as TURP, TUIP and open simple prostatectomy are still performed, market forces have hastened the development of less invasive procedural alternatives, including the demand by urologists for procedural therapies that are easy to learn and provide durable improvements in objective outcomes parameters. Similarly patients desire therapies that provide reasonable clinical efficacy, while limiting the risk of untoward events that historically have made the gold standard treatments comparatively less attractive.35 While current reimbursement methodologies largely discount clinical outcomes and downstream costs, payers are beginning to scrutinize the cost/benefit characteristics of treatment decisions in the context of the emerging pay for performance system. Given the widely held assumption that less invasive procedural options provide acceptable clinical efficacy at substantially decreased risk, they have largely supplanted TURP, TUIP and open simple prostatectomy in the treatment selection process. Few groups have critically evaluated this assumption or the cost-effectiveness of alternative BPH procedural therapies. We have developed a model that meshes traditional objective and subjective measures of the technical success of therapy with a rigorous appraisal of the total cost of care. The model incorporates a data source based on a common methodology derived from a meta-analytic review of the peer reviewed literature for minimally invasive BPH procedural therapy. The calculation of treatment cost, reflecting initial and downstream clinical events, represents a unique economic parameter, which in conjunction with a comparative assessment of clinical outcomes data allows more complete assessment of the cost/benefit characteristics of various procedural BPH therapies. When evaluating clinical outcomes data, we found that ablative BPH treatments, that is procedures designed to remove a large volume of obstructive transition zone tissue, including PVP and TURP, produced more substantive improvement in objective and subjective parameters than thermotherapy, such as ILC, TUNA and TUMT. PVP showed the greatest improvements in AUASS/I-PSS, QMAX and QOL across all intervals. ILC was superior to TUNA and TUMT with respect to AUASS/I-PSS and QMAX. However, TUNA
showed a small QOL advantage over ILC at each interval. In general TUMT produced the least substantive improvements in the outcomes parameters studied. Of the procedural therapies studied PVP was less costly than TURP, ILC, TUNA and TUMT. The cost savings of this procedure stemmed from the rates of adverse events and re-treatment, which on a comparative basis were lower for PVP. Sensitivity analysis revealed several notable findings. Analysis with respect to ILC demonstrated the importance of examining how sites of service can impact the payer cost of BPH procedural therapy. Since ILC is currently typically performed at the physician office site of service, the total cost of this procedure remained higher than that of PVP but lower than that of the other minimally invasive options at all intervals. Also, sensitivity analysis to assess the impact of changes in PVP re-treatment relative to TURP showed that the PVP re-treatment rate required for these procedures to be cost equivalent was more then 3 times greater than the highest re-treatment rate reported in the PVP literature.14 From this we conclude that differences in the expected cost of PVP and TURP are robust to reasonable changes in the rate of PVP re-treatment. Sensitivity analysis to investigate variations in adverse event rates and changes in Medicare reimbursement on total procedural cost produced similar demonstrations of the economic efficiency of PVP. The complexity of the analysis yielded several challenges. While only published peer reviewed material from the AUA guidelines, PVP and ILC literature was abstracted and analyzed using a common general methodology, this type of review did not allow true standardization of data across studies due to certain factors, including the use of prospective and retrospective data, differences in patient cohort demographics, variation in the degree of voiding dysfunction across study populations and discordance in patient co-morbid medical conditions. However, the common methodology ensured consistency in our treatment of adverse event rates and clinical outcomes data for all procedural BPH therapies studied. When considering the economic analysis, our use of Medicare claims file data produced a unique look at adverse event, followup care and re-treatment costs that reflected actual services provided to patients. The result was an unbiased view of the true downstream costs associated with each BPH procedural treatment option. However, we were limited by a lack of contemporaneous Medicare claims file data because information available for public access generally lags real time by several years. As more up to date claims file data become available, model outputs should reflect this new information. Our analysis of Medicare claims file data also necessarily depended on the accuracy of physician and facility reporting/billing practices. However, current reimbursement policies and fee schedules for Medicare and private payers are based on similar nationally reported information. We believe that our use of claims file data represents an accurate and comprehensive means of calculating the total payer costs of the procedural therapies studied. CONCLUSIONS Because physicians and patients are forced to choose from among BPH therapies with widely differing clinical out-
OUTCOME AND COST ANALYSIS OF BENIGN PROSTATIC HYPERPLASIA TREATMENT comes, cost and reimbursement characteristics, tools that add clarity to the treatment selection process are invaluable. Our study using an innovative model to compare procedural treatment options for BPH from outcomes and economic cost perspectives shows that, in comparison to alternative minimally invasive options and TURP, PVP is a clinically efficacious and cost-effective treatment for symptomatic BPH.
10.
11.
12.
Abbreviations and Acronyms AUASS ⫽ American Urological Association symptom score BPH ⫽ benign prostatic hyperplasia CPT ⫽ Physicians’ Current Procedural Terminology ICD-9-CM ⫽ International Classification of Diseases, 9th revision, clinical modification ILC ⫽ interstitial laser coagulation of the prostate I-PSS ⫽ International Prostate Symptom Score PVP ⫽ photoselective vaporization of the prostate QMAX ⫽ maximum uroflowmetry rate QOL ⫽ quality of life score TUMT ⫽ transurethral microwave thermotherapy of the prostate TUNA ⫽ transurethral radio frequency needle ablation of the prostate TURP ⫽ transurethral prostate resection
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