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Recent trends in substance abuse among persons with disabilities compared to that of persons without disabilities
Disability and Health Journal 6 (2013) 107e115 www.disabilityandhealthjnl.com
Research Paper
Recent trends in substance abuse among persons with disabilities compared to that of persons without disabilities Raymond E. Glazier, Ph.D.a,*, and Ryan N. Kling, M.A.b a
disAbility Research Associates, LLC, 59 Underwood Street, Belmont, MA 02478, United States b Abt Associates Inc., 55 Wheeler Street, Cambridge, MA 02138, United States
Abstract Background: Substance abuse (SA) is a grave and pervasive social problem associated with severe personal and social costs that affect persons with disabilities disproportionally. Most previous research has found SA prevalence to be greater among persons with disabilities than among those without disabilities. Objectives: To compare prevalence between persons with disabilities and persons without disabilities for different substances of abuse, and recent SA trends. Methods: The authors examined nine years of nationally representative data estimates from the National Survey on Drug Use and Health, comparing previous month prevalence of self-reported SA on a per-substance basis among community residing persons with disabilities and their peers without disabilities, using a logistic regression model that accounted for demographic factors. Results: Prevalence of overall substance abuse (a composite measure) was level over time, at 34% for persons without disabilities and 40% for persons with disabilities. The SA prevalence among persons with disabilities closely paralleled that of other persons over the period 2002e2010 for each substance examined, but at a statistically significant higher level, with the exception of alcohol abuse, which was significantly lower. Time trends were relatively stable for both populations, with the exception of decreases in cocaine use and recent dramatic increases in marijuana use and oxycodone abuse. Conclusions: Given that substance abuse among persons with disabilities is markedly more prevalent than among other persons for most substances, findings indicate a need for accessible, targeted prevention programs and a potentially overwhelming demand for accessible SA treatment services and facilities. Ó 2013 Elsevier Inc. All rights reserved. Keywords: Disability; Substance abuse; Drug abuse; Survey
The World Health Organization1 has estimated the attributable burden of disease from substance abuse in established market economies like the U.S. conservatively at greater than 23%dfrom tobacco, from alcohol, and from illicit drugs (no mention of prescription drug abuse). Disease burden includes not only additional health care costs, but also lost productivity due to morbidity and mortality.1 Substance abuse especially limits the potential productivity of affected persons
Financial disclosures: This study was funded internally by the U.S. Health Division of Abt Associates Inc. Conflict of interest disclosure: Neither author has any conflict of interest, or appearance thereof, to disclose. An early partial draft of this paper was presented to the Disability Research Interest Group of Academy Health’s Annual Research Meeting on 23 June 2012 at Orlando, FL. * Corresponding author. Tel.: þ1 617 489 1009. E-mail address: [email protected] or ray_glazier@ post.harvard.edu (R.E. Glazier). 1936-6574/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.dhjo.2013.01.007
with disabilities, because, as Li and Moore note in their study of disability and illicit drug use, ‘‘Compared to the general population, individuals with disabilities are more likely to encounter problems of personal adjustment and unemployment, as well as the experienced medical and health difficulties.2’’ It seems self-evident that the widely documented physically and mentally debilitating effects of substance abuse must further compromise the already impaired functional capacity of most persons with disabilities. Previous research has found a much higher proportion of persons with disabilities affected by substance abuse than in the general population, reportedly as great as 87%.3 A decade ago, SAMHSA estimated that as many as 4.7 million Americans with disabilities had a co-occurring substance abuse disorder, and Moore (2002) estimated that 1.5 million persons with disabilities could be in need of substance abuse treatment.4 It is asserted, in a recent (2010) review of the literature on substance abuse and physical disability, that: ‘‘Persons with disabilities are at
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a disproportionately greater risk for substance abuse problems than members of the general population. Substance abuse prevalence rates [sic] in persons with traumatic brain injury, spinal cord injuries and mental illness in the United States approach or exceed 50%.5 This is in comparison to approximately 10% of the general US population. Individuals with deafness, arthritis and multiple sclerosis show substance abuse rates [sic] of at least double general population estimates.6’’ There is a robust, if fragmented literature on the multifaceted relationship between disability and substance abuse. One aspect is substance abuse as a causal factor in disability, e.g., intoxication leading to disabling injury, particularly in auto vehicle crashes: ‘‘Substance misuse/ abuse is also a major contributing factor to many traumatic injuries.alcohol intoxication rates at the time of traumatic brain injury range from 36% to 51%.7,8’’ Another segment of the literature deals with substance abuse as a mediating factor in rehabilitation and recovery, as in addiction impeding the recovery process both for persons with physical and mental health disabilities; vocational rehabilitation is an example of an affected program. ‘‘Post-injury, substance abuse undermines rehabilitation gain.. It may limit rehabilitation outcomes by contributing to functional limitations. Indirect and direct selfdestructive behaviors related to substance abuse.adversely affect the potential for positive rehabilitation outcomes.8’’ It is posited that vocational rehabilitation (VR) systemic factors compound individual ones, namely community VR counselors’ lack of familiarity with substance abuse disorders and rigid requirements for sustained periods of abstinence as a precondition to eligibility for VR services.9 Part of the literature on persons with disabilities treats different substances of abuse separately, viz. alcoholism, IV drugs, prescription drugs. Yet another, less studied aspect is the insufficiency of accessible and appropriate substance abuse treatment services and facilities available to persons with disabilities. Touching on all of the above factors are studies of the prevalence of substance abuse among persons with disabilities in specific sub-populationsdwomen, different racial and ethnic groups, specific disabling conditions (spinal cord injury, traumatic brain injury, learning disabilities, co-occurring mental health conditions like bipolar disorder). The bigger picture is the overall prevalence of substance abuse (SA) in the disability community and how that relates to SA levels among Americans without disabilities, among whom it is a serious public health concern of major proportions. There are numerous published reports that substance abuse is more common among persons with disabilities than in the general population.8,10e12 In fact, some studies have asserted that the prevalence is twice as high or greater (see above). Yet hard data have been difficult to obtain because surveys like the U.S. Census’ Current Population Survey (CPS) that have clear markers for disability status do not track substance abuse. The Behavioral Risk Factor
Surveillance System, which does look at health status and disability (beginning in 2004), examines only tobacco consumption and alcohol abuse, not drug abuse. Data comparability is limited by varying definitions of disability and differing data collection methodologies. Research objective Our intent with this research was to examine trends in substance abuse prevalence, on a per-substance basis, among community-residing persons with disabilities and those without disabilities in order to: a) confirm or contradict previous reports of greater substance abuse prevalence in the disability population, and b) determine whether trends in substance abuse among persons with disabilities diverge from those of the population without disabilities by substance abused and over time. Methods and materials We examined 9 years (2002e2010) of data from the National Survey on Drug Use and Health (NSDUH) to compare difference in the previous month prevalence of: habitual cigarette smoking (6 or more per day, a level SAMHSA seems to consider indicative of habitual smoking), marijuana use, alcohol abuse (binge drinking), use of certain illicit drugs (cocaine, heroin, methamphetamine, hallucinogens, ecstasy), and abuse of four specific classes of prescription drugs (analgesics, sedatives, stimulants, and tranquilizers)dfor adults with disabilities, compared with the general adult residential population. We use ‘abuse’ in connection with consumption of alcohol in inordinate amounts and inappropriate utilization of prescription medications and ‘use’ to refer to consumption of substances defined as illegal by federal statute; we use ‘substance abuse’ as an umbrella term for all of the above. We have defined previous month ‘overall substance abuse’ as habitual cigarette smoking (an average of 6 or more cigarettes per day), alcohol abuse (one or more episodes of binge drinking, i.e., 5 or more drinks at a single sitting), the use of any illicit drug, or abuse of a prescription drug (analgesic, oxycodone, tranquilizer, stimulant, sedative, or psychotherapeutic). The NSDUH statistics are weighted cross-section time series data from a representative, nationwide, householdresiding annual panel survey of in-person interviews with approximately 70,000 randomly selected persons age 12 or older. The NSDUH data are collected during household visits in which each selected age-eligible household member independently responds to the survey privately on a laptop computer. We examined survey responses of working age (18e64) persons, and we defined disability as: a) reported a work disability, or b) age under 65 (non-aged) and Medicareeligible. These two disability markers were the only ones consistently present in the NSDUH over the time frame
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of 2002 through 2010 (the most recent year for which data were available). Psychiatric disability questions were added to the survey in recent years, but we did not utilize these in the interest of employing a consistent disability definition across the study time frame. Although the NSDUH survey methodology has changed slightly from time to time, there were no changes in the study time frame affecting any of the variables we chose to examine. We sought to isolate the association of disability with substance abuse from other personal characteristics, so we used weighted logistic regression to adjust for demographic factors (age group, gender, race/ethnicity, urbanicity of residence, education level, and income level) and dummy variables for survey years. We ‘predicted’ SA for the two groupsecommunity residing working age adults with disabilities and those without disabilitiesefor each substance studied, holding personal characteristics fixed at their overall means across the study time period. Sample validity note SAMHSA considers the NSDUH panel to be nationally representative of the overall U.S. community residing, noninstitutionalized civilian population.13 In order to assess the correspondence of our disability sample, comprised largely of persons who self-identified as having a work disability, to other extant data, we compared each year’s disability total that we obtained from the NSDUH with selfreported work disability estimates from the U. S. Census’ Current Population Survey (CPS). Available disability tallies from other sources either were not aggregated for the same working age population, were based on very different questions, or were derived from very different survey processes and protocols. On balance, our NSDUH disability sample slightly exceeded the CPS estimates, with yearly proportions ranging from a low of 0.937 to a high of 1.489. This was to be expected because we had added to those with a work disability persons under 65 with Medicare eligibility, who could be disabled dependents of disabled workers, or disabled workers who otherwise did not consider themselves to have a work disability, e.g., because of lengthy detachment from the workforce.
Results For each substance studied, self-reported substance abuse in the previous month was greater among persons with disabilities than among their peers without disabilities, with the sole exception of alcohol, for which the significant difference was in the opposite direction. (Persons with disabilities were significantly less likely than their peers to have engaged in binge drinking in the previous month). Table 1 presents the mean percentages of the total observations for each variable in the regression analysis model: Dependent variables include each substance of abuse and
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each grouping of substances, while independent variables include the dummy variable for each survey year, three age groups, gender, race/ethnicity, four education levels, seven income brackets, and three urban residence categories each for the 2002e2004 and 2005e2010 timeframes. For each substance of abuse and grouping of substances in the final year (2010) of this study, Table 2 summarizes the odds ratio between persons with and without disabilities, the lower 95% confidence interval, the upper 95% confidence interval, and the p-value. The following graphs are regression-adjusted estimates of the percentage of the population admitting to previous month substance abuse, evaluated at the overall mean of the independent variables, evaluated separately for those persons with and without a disability (as we defined disability). Note: These are national estimates, regressionadjusted for age group, gender, race/ethnicity, education level, income level, and residential urbanicity. The measure for previous month prevalence of overall substance abuse, graphed in Fig. 1 below, is inclusive of habitual cigarette smoking (6 or more per day), binge drinking (5 or more drinks at a single sitting), illicit drug use (powder cocaine, crack cocaine, heroin, methamphetamine, hallucinogens, or ecstasy), and prescription drug abuse (analgesics, oxycodone, sedatives, stimulants, or tranquilizers). Substance abuse in some form is alarmingly prevalent and stable over recent years, involving more than a third (34%) of the population without disabilities and 40% of persons with disabilities. Consistently across all 9 years, persons with disabilities were more likely than those without disabilities to admit some form of substance abuse; for example, the 2010 odds ratio for overall substance abuse was 1.28, with a 95% confidence interval of 1.19 to 1.37 ( p ! 0.001). Among persons without disabilities, the previous month prevalence of habitual cigarette smoking (6 or more cigarettes per day) decreased from about 14%e12% over the nine years. However, for persons with disabilities, the prevalence began at 20% in 2002, rose to a high of 22% in 2004, and then fell back to 20% once again. Consistently across all 9 years, persons with disabilities were much more likely than those without disabilities to smoke 6 or more cigarettes daily; the 2010 odds ratio was 1.83, with a 95% confidence interval of 1.68e1.99 ( p ! 0.001). Over time, the general trend for cigarette smoking at this level per day decreased significantly ( p ! 0.0001) for both populations, although the decrease was not as great among persons with disabilities. Alcohol was the only substance in this study for which estimates of the previous month prevalence of abuse (binge drinking) was lesser for persons with disabilities, ranging from 18% in the early years to 19% in later years, than that of persons without disabilities, which averaged about 21.5% in the study’s early years and reached its peak of 24% in 2009. Persons with disabilities were less likely than those without disabilities to admit having engaged in binge
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Table 1 Means of NSDUH regression analysis variables, 2002e2010 Variable a
Number of observations (unweighted) Dependent variables’ mean prevalence Any substance abuse in past month (prescription or illicit drugs, binge alcohol, or habitual cigarette smoking) Average of 6 cigarettes a day, past month Binge drinking in past month Marijuana use in past month Cocaine, crack, heroin, or meth, past month Powder cocaine use in past month Crack cocaine use in past month Powder or crack cocaine use in past month Heroin use in past month Methamphetamine use in past month Hallucinogens use in past month Ecstasy use in past month Any illicit drug use in past month (marijuana, powder or crack cocaine, heroin, methamphetamine, hallucinogens, or ecstasy) Alcohol abuse or any illicit drug use, past month Analgesics Oxycodone Tranquilizers Stimulants Sedatives Psychotherapeutics Independent variables’ mean frequencies Year dummy: 2002 Year dummy: 2003 Year dummy: 2004 Year dummy: 2005 Year dummy: 2006 Year dummy: 2007 Year dummy: 2008 Year dummy: 2009 Year dummy: 2010 Age 18e25 Age 26e34 Age 35 or more Male Female White Black/African American Hispanic Other race Education: Less than HS Education: HS graduate Education: some college Education: college graduate and higher Income: less than $10,000 per annum Income: $10,000e$20,000 per annum Income: $20,000e$30,000 per annum Income: $30,000e$40,000 per annum Income: $40,000e$50,000 per annum Income: $50,000e$75,000 per annum Income: more than $75,000 per annum Large urban area, 2004 or earlier Small urban area, 2004 or earlier Not an urban area, 2004 or earlier Large urban area, 2005 or later Small urban area, 2005 or later Not an urban area, 2005 or later a
Without disability
With disability
316,746
20,904
The maximum number of observations for the analysis. Some variables (e.g., oxycodone) have fewer.
0.355
0.403
0.156 0.248 0.061 0.010 0.008 0.002 0.008 0.001 0.002 0.004 0.002 0.065
0.276 0.179 0.067 0.020 0.016 0.009 0.016 0.003 0.003 0.003 0.001 0.077
0.266 0.018 0.002 0.007 0.004 0.001 0.025
0.214 0.028 0.003 0.013 0.005 0.003 0.037
0.108 0.109 0.110 0.111 0.113 0.113 0.112 0.113 0.113 0.153 0.166 0.681 0.483 0.517 0.704 0.105 0.129 0.062 0.150 0.309 0.257 0.284 0.058 0.107 0.114 0.118 0.117 0.186 0.301 0.148 0.108 0.070 0.354 0.276 0.043
0.088 0.087 0.091 0.095 0.097 0.108 0.137 0.142 0.155 0.081 0.102 0.817 0.464 0.536 0.593 0.219 0.139 0.049 0.325 0.370 0.208 0.097 0.211 0.274 0.152 0.109 0.082 0.091 0.081 0.101 0.088 0.077 0.334 0.333 0.067
R.E. Glazier and R.N. Kling / Disability and Health Journal 6 (2013) 107e115 Table 2 2010 odds ratios for differences between persons with and without disability Measure (abuse in past month) e 2010 results
Odds ratio Lower 95% CI Upper 95% CI p-value
Any substance abuse (prescription or Illicit drugs, Binge alcohol, or Habitual cigarette smoking) 1.280 Ave. 6 cigarettes/day in month 1.828 Binge drinking in past month 0.780 Marijuana use in past month 1.430 Cocaine, crack, heroin, or meth. 2.340 Powder cocaine 2.190 Crack cocaine 2.599 Powder or Crack cocaine 2.190 Heroin 4.715 Methamphetamine 2.630 Hallucinogens 0.924 Ecstasy 0.799 Any illicit drug (marijuana, powder or crack cocaine, heroin, methamphetamine, 1.480 hallucinogens, or ecstasy) Alcohol binge or any illicit drug 0.892 Analgesics 1.648 Oxycodone 3.035 Tranquilizers 2.038 Stimulants 1.638 Sedatives 3.008 Psychotherapeutics 1.625
drinking (5 or more drinks in one sitting) at least once in the previous month; the 2010 odds ratio was 0.78, with a 95% confidence level of 0.72 to 0.85 ( p ! 0.001). Note the more finely gradated scale of the X-axis, reflective of the lesser prevalence. There is a dramatic relative decline in the previous month prevalence of abuse of this group of four illegal drugs, with the trend for persons with disabilities very closely paralleling that for other persons. For persons without disabilities, the prevalence estimates fell rather steadily from 1.1% in 2002 to 0.4% in 2010. Comparatively, prevalence estimates for persons with disabilities declined to essentially the same degree over the period, from an initial high of 1.7% to 1.0%. Persons with disabilities were much more likely to admit to use of these four major illicit drugs than persons without disabilities, even as use declined in both populations; the 2010 odds ratio was 2.34, with a 95% confidence interval of 1.81 to 3.03 ( p ! 0.001). Both groups started the time period with very comparable estimated prevalence of marijuana use: 4.4% among persons without disabilities and 4.5% among persons with disabilities in 2002. However, over the nine-year span, persons with disabilities were much more likely to admit to having used marijuana in the previous month than persons without disabilities; the 2010 odds ratio was 1.43, with a 95% confidence interval of 1.26 to 1.63 ( p ! 0.001). There was a statistically significant upward trend overall ( p 5 0.0090) for marijuana use in both populations. However, the trajectory for persons with disabilities diverged from that of other persons ( p 5 0.0167) and showed a markedly steep path, ending at 6.6% in 2010 for a major (43%) difference in usage between the two populations in the last year of the study.
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1.194 1.682 0.716 1.258 1.805 1.632 1.683 1.632 2.581 1.622 0.619 0.439 1.308
1.371 1.987 0.849 1.625 3.033 2.937 4.012 2.937 8.612 4.266 1.380 1.455 1.675
!0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 0.700 0.463 !0.001
0.821 1.350 1.760 1.595 1.186 1.817 1.402
0.969 2.010 5.233 2.606 2.262 4.978 1.884
0.007 !0.001 !0.001 !0.001 0.003 !0.001 !0.001
Among the individual illicit and prescription drugs we studied, the 2010 odds ratios for difference in selfreported use/abuse between persons with disabilities and those without disabilities were in some cases strikingly large and statistically significant (Reference Table 2 above.). For example (in descending order): Heroin, with an odds ratio of 4.72, 95% confidence interval of 2.58 to 8.61 ( p ! 0.001); Oxycodone, with an odds ratio of 3.01, 95% confidence interval of 1.76 to 5.23 ( p ! 0.001); Sedatives, with an odds ratio of 3.02, 95% confidence interval of 1.82 to 4.98 ( p O 0.001); Methamphetamine, with an odds ratio of 2.63, 95% confidence interval of 1.62 to 4.23 ( p ! 0.001); Crack cocaine, with an odds ratio of 2.60, 95% confidence interval of 1.68 to 4.01 ( p ! 0.001);
Fig. 1. Overall substance abuse e any drug abuse (prescription or illicit), smoking, or binge alcohol in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
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Powder Cocaine, with an odds ratio of 2.19, 95% confidence interval of 1.63 to 2.94 ( p ! 0.001); Tranquilizers, with an odds ratio of 2.04, 95% confidence interval of 1.60 to 2.61 ( p ! 0.001); Analgesics, with an odds ratio of 1.65, 95% confidence interval of 1.35 to 2.01 ( p ! .001); Stimulants, with an odds ratio of 1.64, 95% confidence interval of 1.19 to 2.28 ( p ! 0.001) and; Psychotherapeutics, with an odds ratio of 1.63, 95% confidence interval of 1.40 to 1.88 ( p ! 0.001).
Substance abuse of all types, including abuse of prescription drugs, is an even greater problem in the disability community than in the U.S. population at large. However, trends over the study time frame for both populations were pretty much parallel, with the notable exception of marijuana use (recreational or medical) and oxycodone abuse in the later years of the study; both marijuana use and oxycodone abuse accelerated sharply in the later years, and the prevalence among persons with disabilities diverged widely upward from that of other persons. It is notable that abuse of different classes of prescription drugs ranks prominently in the 2010 per-substance odds ratios between self-reports of persons with disabilities compared to that of other persons. Overall substance abuse (Please see Fig. 1.)dThe finding of significantly higher abuse prevalence (33% greater) among persons with disabilities is largely driven by their greater levels of habitual cigarette smoking, greater use of cocaine, and more frequent abuse of psychotherapeutic prescription drugs. There was no statistically significant time trend on this multi-factor measure, either for persons with disabilities or other persons. Cigarette smoking (Please see Fig. 2.)dSince WHO1 attributes the lion’s share of disease burden (19.2% of the roughly 23% total) to tobacco, the downward trend among persons without disabilities is somewhat encouraging, whereas the rather level trend in cigarette smoking by
persons with disabilities is not. This is a key substance of abuse, and in the world at large, it is on a steep trajectory as a major risk factor for greater morbidity and mortality.1 Some psychosocial research has attributed the higher level of smoking among persons with disabilities, and the greater prevalence of overall substance abuse, to a sense of personal ‘entitlement’ among persons with disabilities.2 In their research with Midwestern vocational rehabilitation consumers with significant disabilities, Li and Moore (2001) applied the concept of ‘secondary deviance’ in their examination of disability, ‘entitlement,’ and illicit drug use, concluding that: ‘‘.perceived discrimination and acceptance of disability play important roles in illicit drug use by persons with disabilities.14’’ They relate this phenomenon to the stigma, discriminatory labeling, and internalization of negative stereotypes experienced by other minority groups. Moore and Li measured the degree to which their survey sample felt that their stigmatized status ‘entitled’ them to engage in substance abuse by degree of agreement with the following survey statements: ‘‘1) People with disabilities have more reasons to use alcohol or other drugs than those without disabilities; 2) Because I have a disability, I sometimes feel that I have less to lose and more to gain from using alcohol or other drugs; and 3) People with disabilities already have many problems, so alcohol or drug use is not a big deal.’’ Alcohol abuseebinge drinking (Please see Fig. 3.)dThe lesser prevalence of binge drinking among persons with disabilities is a consistent and notable counter trend to the general pattern observed for other substances of abuse. Prevalence of binge drinking has remained essentially constant and parallel over this 9-year time frame for both populations. The National Health Interview Survey found a comparable alcohol abuse percentage (22.8) for the general civilian non-institutionalized population in 2009.15 The Behavioral Risk Factor Surveillance System (BRFSS) found a lower adult binge drinking prevalence, 15.2%, for 2009, probably due to the inclusion of persons over 65, who engage in this activity much less frequently. But the BRFSS also found an even lower prevalence (14.3%)
Fig. 2. Cigarette smoking e average 6 or more cigarettes per day in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Fig. 3. AlcoholeBinge drinking (5 or more drinks at one sitting) in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Discussion
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16
among persons with disabilities. Other researchers comparing earlier binge drinking prevalence estimates from both the BRFSS and the NSDUH imply that the more confidential NSDUH interview process may account for that survey’s higher numbers.17 ‘‘Big Four’’ substance abuse (powder cocaine, crack, heroin, or methamphetamine) (Please see Fig. 4.)dAbuse of one of this group of four major illicit ‘street drugs’ is an indicator of serious drug addiction with criminal justice implications, not only because their very use is illegal, but because users often need to engage in other criminal behavioretheft or prostitutioneto support their habits. Note that, although the overall percentage admitting to use is much smaller for both populations than with other substances of abuse, the absolute numbers of users are strikingly large. In per-substance analyses, we found that the illicit drug trends for both groups were largely driven by the decrease in cocaine use (both powder and crack cocaine). Any marijuana use (Please see Fig. 5.)dIn both populations, there was an increase in previous month prevalence in the later years, an especially marked one for persons with disabilities. The trends for the two populations diverge dramatically in the later years, following medical marijuana legalization legislation in certain states (16 states þ D.C. by 2010), which might mean readier, perhaps subsidized medical marijuana availability for persons with disabilities. Strengths and limitations Among the great strengths of the NSDUH are its regular annual administration, the confidentiality provisions for self-reporting, and its great detail on the many forms of substance abuse, as well as its purposefully low 6th grade literacy level. For purposes of research focusing on the disability population, a significant limitation is its dearth of detail on the disability status of respondents. And, while the survey sample is selected to be nationally representative on various demographic dimensions, disability status is not a sampling factor. As noted earlier, the only question directly addressing disability consistently across the period
Fig. 4. ‘Big Four’ substance abuse (powder cocaine, crack, heroin, or methamphetamine) use in the previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Fig. 5. Any marijuana use, including medical use in later years (regression-adjusted estimates from NSDUH, 2002e2010).
2002e2010 is whether the respondent is not working because of ‘work disability’.5 Our measure of disability is generally driven by work disability. This is in part a matter of practicality, as that is the measurement consistently available in the data across the time frame of the analysis. But this ‘limitation’ is also fortuitous, as the working age population constitutes an interesting group for policy study, and potentially for policy interventions related to the improvement of national economic productivity and the preservation of the Social Security Trust funds. Since having a work disability is often associated with very painful conditions like musculoskeletal disorders, our estimated odds ratios for those drugs, which are most prescribed for pain (analgesics, oxycodone) may be larger than if we had a differently defined disability population. Similarly, our estimated odds ratios for drugs which are most often prescribed for psychiatric conditions (psychotherapeutics) may be lower than if we had a differently defined disability population, e.g., if we had used the mental health markers introduced in the 2007 NSDUH. Overall, we may be generally understating the difference in substance abuse between those with and without disabilities, since it appears that NSDUH does not capture anyone whose disabilities are too burdensome to allow them to participate in the interview. Some of these non-respondents could have been those with the most significant physical and mental disabilities. Furthermore, the data reports make note of interviewer codes for ‘physically/mentally incompetent,’ classifications implemented at interviewer discretion,5 which may have introduced distortion through underinclusion of persons with severe disabilities; it is unclear in what ways this may have affected the findings of this study. Another complication arising from the NSDUH survey protocol is inaccessibility or potential loss of confidentiality for respondents with sensory disabilities because the instructions for self-administration of the survey are provided in an audio file inaccessible to persons who are deaf or severely hard of hearing, whereas the self-administered questions and response options on the laptop are provided visually, inaccessible to persons who are blind or have severe vision
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impairment. Persons with severe motor impairments likewise could have had their confidentiality compromised by being unable to register their self-reports without assistance from the interviewer or a fellow household member. Nonresponses or loss of confidentiality could also contribute to under-reporting of substance abuse. Furthermore, the exclusion of institutionalized persons is an understandable limitation that could have mixed effects on our findings, as these persons may have ready access to certain substances of abuse (e.g., cigarettes) and more restricted access to others (e.g., alcoholic beverages and prescription drugs that are administered in a carefully controlled manner). The survey’s inclusion, beginning in 2007, of mental health status measures opens up new avenues for research, e.g., utilizing NSDUH data to examine the complex relationship between different psychiatric disabilities and different forms of substance abuse, including trends over time. Similarly, the relationship between different nonpsychiatric disabilities and different types of substance abuse would become possible if the NSDUH were to include a comprehensive battery of disability questions. Access improvements in survey administration could improve the response rate among persons with disabilities and affect self-reported substance abuse in this population by ensuring improved confidentiality of responses.
Conclusions Over the period 2002e2010, the substance abuse trends for persons with disabilities, with a few notable exceptions, closely paralleled those for other persons in the U.S. residential population, but at a significantly higher level. The comprehensive substance abuse trend was level for both populations, but trends were down for: cigarette smoking, cocaine (both powder and crack), hallucinogens, and ecstasy for both persons with and without disabilities. The implication of these findings is that over time there are shifts in preference among specific substances of abuse that neither raise nor lower the overall abuse profile of either group. The previous month prevalence of substance abuse among persons with disabilities differed from that of other persons in significantly higher percentages of overall substance abuse, habitual cigarette smoking, use of the group of major illicit drugs, and marijuana use, with a significantly lower percentage of binge drinking. These differences were persistent across the time frame (2002e2010). There is good reason to believe (see study limitations above) that the underreporting of substance abuse is a more frequently occurring phenomenon among persons with disabilities than among the general population. Implications There seems to be no reason to question the face validity of the NSDUH self-reports of substance abuse, but only the
volume of them. Respondents have nothing to gain by privately admitting to behaviors generally regarded as socially deviant. Nor is there reason to believe that persons with disabilities have any reason to exaggerate their substance abuse behaviors. Therefore, it is apparent that overall substance abuse, while it is not normative behavior, is very common in the general population (1 in 3 persons) and even more common among persons with disabilities (2 in 5 persons). Examination of the substance-specific trends for the disability community can inform differential messaging and appropriate, accessible substance abuse prevention programs for persons with disabilities. Given the findings reported herein, the multitude of debilitating effects of cigarette smoking, and both the direct health care costs and the lost productivity implications of smoking, combined with the relatively low cost of tobacco cessation programs, the importance of promoting smoking cessation through culturally competent messaging via accessible media cannot be overemphasized. Other major substance abuse prevention priority targets for appropriate messaging to the disability community via accessible media include: 1) dangers of heroin use and inherent addiction (including the HIV/AIDS hazard from shared needles) and the benefits of methadone treatment; 2) the powerful addiction potential of oxycodone in the various forms in which it is abused (ingestion, inhalation, IV injection) and treatment and recovery options; 3) the problems associated with use of highly addictive methamphetamine and cocaine (powder and crack) and treatment/rehabilitation options; and 4) preventing abuse of prescription drugs to which many persons with disabilities have legitimate accesse sedatives, tranquilizers, analgesics (painkillers), stimulants, and psychotherapeuticsein the form both of self- abuse through misuse, overuse, super-dose, as well as facilitating abuse by others through inattention to missing medications ‘borrowed’ by friends or family, or intentional diversion of prescription medications into street trafficking for profit. Similarly, the trends document the increasing need for accessible substance abuse treatment facilities and programs, and appropriate treatment and recovery services that accurately target persons with disabilities’ different forms and patterns of abuse. The woeful inadequacy of accessible SA treatment facilities and programs in the U.S. was recently documented in a nationally representative survey: ‘‘Most responding facilities self-reported a variety of barriers to physical accessibility, as well as the lack of services and physical accommodations for persons with sensory limitations. Such widespread inaccessibility may be a factor that promotes the low representation of persons with disabilities in the treatment population.18’’ Extrapolating the prevalence we found to the U.S. Census 2010 estimate that there were 19,048,426 civilian non-institutionalized persons with disabilities,19 if all such persons with any form of substance abuse (40.3%) had sought treatment, the national caseload for only persons
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with disabilities would have been 7,676,516. If, more conservatively, only persons who reported that they used illicit drugs or abused alcohol in 2010 (21.4%) applied for alcohol or drug abuse treatment services, that disability caseload would have been 4,076,363. For some substances of abuse, there are day treatment programs, new detoxification protocols, new pharmaceuticals (e.g., Naltrexone, introduced over a decade ago for treatment of alcoholism and opioid dependence), 12-step programs, alternative therapies like acupuncture, and other options short of inpatient treatment. Peer support and peer counseling can be crucially important in the treatment and recovery process. We suppose that many persons with disabilities who are in recovery might have difficulty finding true peers with whom to share their experience and provide needed social support, other persons with the same type of disability and the same substance abuse issues. The message of hope for recovery through the various available substance abuse treatment modalities is something all affected persons need to hear. Persons with disabilities, their families, and friends must be afforded the same opportunity.
6.
7. 8.
9.
10.
11.
12.
13.
Acknowledgments Credit is due to the Substance Abuse and Mental Health Services Administration (SAMHSA) of the U.S. Department of Health and Human Services for its long-term commitment to sponsoring the National Survey on Drug Use and Health (NSDUH) and its predecessor, the National Household Survey on Drug Abuse (NHSDA). References 1. World Health Organization. World Health Report 2002: Reducing Risks, Promoting Healthy Life, http://www.who.int/whr/2002/en/ whr02_en.pdf; 2002. Accessed 29.06.12. 2. Li L, Moore D. Page 5 in: Disability and illicit drug use: an application of labeling theory. Deviant Behavior. 2001;22:1e21. 3. Alcoholism & Drug Abuse Weekly; August 15, 2005. p. 3. 4. Office on Disability, U.S. Department of Health and Human Services (Undated). Substance abuse and disability: a companion to chapter 26 of healthy people 2010. http://www.hhs.gov/od/about/fact_sheets/ substanceabusech26.html; Accessed 22.03.12. 5. Office of Applied Statistics, Substance Abuse and Mental Health Services Administration (SAMHSA). National Survey on Drug Use
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and Health: Methodology Reports and Questionnaires, http://www. oas.samhsa.gov/nsduh/methods.cfm#2k2; 29 Dec 2009. Accessed 12.11.12. Smedema SM, Ebener D. Pages 1311e1312 in: Substance abuse and psychosocial adaptation to physical disability: analysis of the literature and future directions. Disabil Rehabil. 2010;32(16): 1311e1319. Corrigan JD. Substance abuse as a mediating factor in outcome from traumatic brain injury. Arch Phys Med. 1995;76(4):302e309. Smedema SM, Ebener D. Substance abuse and psychosocial adaptation to physical disability: analysis of the literature and future directions. Disabil Rehabil. 2010;32(16):1312. Ateron WL, Toriello PJ, Sligar SR, Campbell TE. Use of the addiction severity index in vocational evaluation for persons with substance use disorders. VEWAA J. 2010;437(1):18e25. Gilson SF, Chilcoat HD, Stapleton JM. Illicit drug use by persons with disabilities: insights from the National Household Survey on Drug Abuse. Am J Publ Health. 1996;86(11):1613e1615. Moore D, Greer B, Li L. Alcohol and other substance use/abuse among people with disabilities. Psychosocial Perspectives on Disabilities. 1994;9:369e382. Hubbard JR, Everett AS, Khan MA. Alcohol and drug abuse in patients with physical disabilities. Am J Drug Alcohol Abuse. 1996;22(2):215e231. SAMHSA/DHHS. Results from the 2009 National Survey on Drug Use and Health: Volume II. Technical Appendices and Selected Prevalence Tables, http://www.samhsa.gov/data/NSDUH/ 2k9NSDUH/2k9ResultsApps.htm; September 2010. Accessed 06.07.12. Li and Moore. Page 1 in: Disability and illicit drug use: an application of labeling theory. Deviant Behavior. 2001;22:1e21 [survey statements quoted, p. 9]. Centers for Disease Control. Alcohol Consumption, Fig. 9.1. Percentage of adults aged 18 and over who had five or more drinks in 1 day at least once in the past year: United States, 1997e2011, second note. Accessed 06.07.12. N.B.: The inclusion of persons over 65 lowers the percentage, http://www.cdc.gov/nchs/data/nhis/ earlyrelease/earlyrelease201206_09.pdf; 2012. Kanny D, Liu Y, Brewer RD. Binge drinkingdUnited States, 2009. Morbidity & Mortality Weekly Report(1):101e104 [see Tables 1 and 2], http://www.cdc.gov/mmwr/preview/mmwrhtml/su6001a22.htm?s_ cid5su6001a22_w, 2011;60. Accessed 06.07.12. Miller JW, Gfroerer JC, Brewer RD, Naimi TS, Mokdad A, Giles WH. Prevalence of adult binge drinking: a comparison of two national surveys. Am J Prev Med. 2004;27(3):197e204. West SL. Page 1 in: The accessibility of substance abuse treatment facilities in the United States for persons with disabilities. J Subst Abuse Treat. 2007;33(1):1e5. U.S. Census Bureau. American Community Survey, American Fact Finder, Table B18101, http://www.factfinder.census.gov; 2010 Accessed 17.09.11.
Research Paper
Recent trends in substance abuse among persons with disabilities compared to that of persons without disabilities Raymond E. Glazier, Ph.D.a,*, and Ryan N. Kling, M.A.b a
disAbility Research Associates, LLC, 59 Underwood Street, Belmont, MA 02478, United States b Abt Associates Inc., 55 Wheeler Street, Cambridge, MA 02138, United States
Abstract Background: Substance abuse (SA) is a grave and pervasive social problem associated with severe personal and social costs that affect persons with disabilities disproportionally. Most previous research has found SA prevalence to be greater among persons with disabilities than among those without disabilities. Objectives: To compare prevalence between persons with disabilities and persons without disabilities for different substances of abuse, and recent SA trends. Methods: The authors examined nine years of nationally representative data estimates from the National Survey on Drug Use and Health, comparing previous month prevalence of self-reported SA on a per-substance basis among community residing persons with disabilities and their peers without disabilities, using a logistic regression model that accounted for demographic factors. Results: Prevalence of overall substance abuse (a composite measure) was level over time, at 34% for persons without disabilities and 40% for persons with disabilities. The SA prevalence among persons with disabilities closely paralleled that of other persons over the period 2002e2010 for each substance examined, but at a statistically significant higher level, with the exception of alcohol abuse, which was significantly lower. Time trends were relatively stable for both populations, with the exception of decreases in cocaine use and recent dramatic increases in marijuana use and oxycodone abuse. Conclusions: Given that substance abuse among persons with disabilities is markedly more prevalent than among other persons for most substances, findings indicate a need for accessible, targeted prevention programs and a potentially overwhelming demand for accessible SA treatment services and facilities. Ó 2013 Elsevier Inc. All rights reserved. Keywords: Disability; Substance abuse; Drug abuse; Survey
The World Health Organization1 has estimated the attributable burden of disease from substance abuse in established market economies like the U.S. conservatively at greater than 23%dfrom tobacco, from alcohol, and from illicit drugs (no mention of prescription drug abuse). Disease burden includes not only additional health care costs, but also lost productivity due to morbidity and mortality.1 Substance abuse especially limits the potential productivity of affected persons
Financial disclosures: This study was funded internally by the U.S. Health Division of Abt Associates Inc. Conflict of interest disclosure: Neither author has any conflict of interest, or appearance thereof, to disclose. An early partial draft of this paper was presented to the Disability Research Interest Group of Academy Health’s Annual Research Meeting on 23 June 2012 at Orlando, FL. * Corresponding author. Tel.: þ1 617 489 1009. E-mail address: [email protected] or ray_glazier@ post.harvard.edu (R.E. Glazier). 1936-6574/$ - see front matter Ó 2013 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.dhjo.2013.01.007
with disabilities, because, as Li and Moore note in their study of disability and illicit drug use, ‘‘Compared to the general population, individuals with disabilities are more likely to encounter problems of personal adjustment and unemployment, as well as the experienced medical and health difficulties.2’’ It seems self-evident that the widely documented physically and mentally debilitating effects of substance abuse must further compromise the already impaired functional capacity of most persons with disabilities. Previous research has found a much higher proportion of persons with disabilities affected by substance abuse than in the general population, reportedly as great as 87%.3 A decade ago, SAMHSA estimated that as many as 4.7 million Americans with disabilities had a co-occurring substance abuse disorder, and Moore (2002) estimated that 1.5 million persons with disabilities could be in need of substance abuse treatment.4 It is asserted, in a recent (2010) review of the literature on substance abuse and physical disability, that: ‘‘Persons with disabilities are at
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a disproportionately greater risk for substance abuse problems than members of the general population. Substance abuse prevalence rates [sic] in persons with traumatic brain injury, spinal cord injuries and mental illness in the United States approach or exceed 50%.5 This is in comparison to approximately 10% of the general US population. Individuals with deafness, arthritis and multiple sclerosis show substance abuse rates [sic] of at least double general population estimates.6’’ There is a robust, if fragmented literature on the multifaceted relationship between disability and substance abuse. One aspect is substance abuse as a causal factor in disability, e.g., intoxication leading to disabling injury, particularly in auto vehicle crashes: ‘‘Substance misuse/ abuse is also a major contributing factor to many traumatic injuries.alcohol intoxication rates at the time of traumatic brain injury range from 36% to 51%.7,8’’ Another segment of the literature deals with substance abuse as a mediating factor in rehabilitation and recovery, as in addiction impeding the recovery process both for persons with physical and mental health disabilities; vocational rehabilitation is an example of an affected program. ‘‘Post-injury, substance abuse undermines rehabilitation gain.. It may limit rehabilitation outcomes by contributing to functional limitations. Indirect and direct selfdestructive behaviors related to substance abuse.adversely affect the potential for positive rehabilitation outcomes.8’’ It is posited that vocational rehabilitation (VR) systemic factors compound individual ones, namely community VR counselors’ lack of familiarity with substance abuse disorders and rigid requirements for sustained periods of abstinence as a precondition to eligibility for VR services.9 Part of the literature on persons with disabilities treats different substances of abuse separately, viz. alcoholism, IV drugs, prescription drugs. Yet another, less studied aspect is the insufficiency of accessible and appropriate substance abuse treatment services and facilities available to persons with disabilities. Touching on all of the above factors are studies of the prevalence of substance abuse among persons with disabilities in specific sub-populationsdwomen, different racial and ethnic groups, specific disabling conditions (spinal cord injury, traumatic brain injury, learning disabilities, co-occurring mental health conditions like bipolar disorder). The bigger picture is the overall prevalence of substance abuse (SA) in the disability community and how that relates to SA levels among Americans without disabilities, among whom it is a serious public health concern of major proportions. There are numerous published reports that substance abuse is more common among persons with disabilities than in the general population.8,10e12 In fact, some studies have asserted that the prevalence is twice as high or greater (see above). Yet hard data have been difficult to obtain because surveys like the U.S. Census’ Current Population Survey (CPS) that have clear markers for disability status do not track substance abuse. The Behavioral Risk Factor
Surveillance System, which does look at health status and disability (beginning in 2004), examines only tobacco consumption and alcohol abuse, not drug abuse. Data comparability is limited by varying definitions of disability and differing data collection methodologies. Research objective Our intent with this research was to examine trends in substance abuse prevalence, on a per-substance basis, among community-residing persons with disabilities and those without disabilities in order to: a) confirm or contradict previous reports of greater substance abuse prevalence in the disability population, and b) determine whether trends in substance abuse among persons with disabilities diverge from those of the population without disabilities by substance abused and over time. Methods and materials We examined 9 years (2002e2010) of data from the National Survey on Drug Use and Health (NSDUH) to compare difference in the previous month prevalence of: habitual cigarette smoking (6 or more per day, a level SAMHSA seems to consider indicative of habitual smoking), marijuana use, alcohol abuse (binge drinking), use of certain illicit drugs (cocaine, heroin, methamphetamine, hallucinogens, ecstasy), and abuse of four specific classes of prescription drugs (analgesics, sedatives, stimulants, and tranquilizers)dfor adults with disabilities, compared with the general adult residential population. We use ‘abuse’ in connection with consumption of alcohol in inordinate amounts and inappropriate utilization of prescription medications and ‘use’ to refer to consumption of substances defined as illegal by federal statute; we use ‘substance abuse’ as an umbrella term for all of the above. We have defined previous month ‘overall substance abuse’ as habitual cigarette smoking (an average of 6 or more cigarettes per day), alcohol abuse (one or more episodes of binge drinking, i.e., 5 or more drinks at a single sitting), the use of any illicit drug, or abuse of a prescription drug (analgesic, oxycodone, tranquilizer, stimulant, sedative, or psychotherapeutic). The NSDUH statistics are weighted cross-section time series data from a representative, nationwide, householdresiding annual panel survey of in-person interviews with approximately 70,000 randomly selected persons age 12 or older. The NSDUH data are collected during household visits in which each selected age-eligible household member independently responds to the survey privately on a laptop computer. We examined survey responses of working age (18e64) persons, and we defined disability as: a) reported a work disability, or b) age under 65 (non-aged) and Medicareeligible. These two disability markers were the only ones consistently present in the NSDUH over the time frame
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of 2002 through 2010 (the most recent year for which data were available). Psychiatric disability questions were added to the survey in recent years, but we did not utilize these in the interest of employing a consistent disability definition across the study time frame. Although the NSDUH survey methodology has changed slightly from time to time, there were no changes in the study time frame affecting any of the variables we chose to examine. We sought to isolate the association of disability with substance abuse from other personal characteristics, so we used weighted logistic regression to adjust for demographic factors (age group, gender, race/ethnicity, urbanicity of residence, education level, and income level) and dummy variables for survey years. We ‘predicted’ SA for the two groupsecommunity residing working age adults with disabilities and those without disabilitiesefor each substance studied, holding personal characteristics fixed at their overall means across the study time period. Sample validity note SAMHSA considers the NSDUH panel to be nationally representative of the overall U.S. community residing, noninstitutionalized civilian population.13 In order to assess the correspondence of our disability sample, comprised largely of persons who self-identified as having a work disability, to other extant data, we compared each year’s disability total that we obtained from the NSDUH with selfreported work disability estimates from the U. S. Census’ Current Population Survey (CPS). Available disability tallies from other sources either were not aggregated for the same working age population, were based on very different questions, or were derived from very different survey processes and protocols. On balance, our NSDUH disability sample slightly exceeded the CPS estimates, with yearly proportions ranging from a low of 0.937 to a high of 1.489. This was to be expected because we had added to those with a work disability persons under 65 with Medicare eligibility, who could be disabled dependents of disabled workers, or disabled workers who otherwise did not consider themselves to have a work disability, e.g., because of lengthy detachment from the workforce.
Results For each substance studied, self-reported substance abuse in the previous month was greater among persons with disabilities than among their peers without disabilities, with the sole exception of alcohol, for which the significant difference was in the opposite direction. (Persons with disabilities were significantly less likely than their peers to have engaged in binge drinking in the previous month). Table 1 presents the mean percentages of the total observations for each variable in the regression analysis model: Dependent variables include each substance of abuse and
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each grouping of substances, while independent variables include the dummy variable for each survey year, three age groups, gender, race/ethnicity, four education levels, seven income brackets, and three urban residence categories each for the 2002e2004 and 2005e2010 timeframes. For each substance of abuse and grouping of substances in the final year (2010) of this study, Table 2 summarizes the odds ratio between persons with and without disabilities, the lower 95% confidence interval, the upper 95% confidence interval, and the p-value. The following graphs are regression-adjusted estimates of the percentage of the population admitting to previous month substance abuse, evaluated at the overall mean of the independent variables, evaluated separately for those persons with and without a disability (as we defined disability). Note: These are national estimates, regressionadjusted for age group, gender, race/ethnicity, education level, income level, and residential urbanicity. The measure for previous month prevalence of overall substance abuse, graphed in Fig. 1 below, is inclusive of habitual cigarette smoking (6 or more per day), binge drinking (5 or more drinks at a single sitting), illicit drug use (powder cocaine, crack cocaine, heroin, methamphetamine, hallucinogens, or ecstasy), and prescription drug abuse (analgesics, oxycodone, sedatives, stimulants, or tranquilizers). Substance abuse in some form is alarmingly prevalent and stable over recent years, involving more than a third (34%) of the population without disabilities and 40% of persons with disabilities. Consistently across all 9 years, persons with disabilities were more likely than those without disabilities to admit some form of substance abuse; for example, the 2010 odds ratio for overall substance abuse was 1.28, with a 95% confidence interval of 1.19 to 1.37 ( p ! 0.001). Among persons without disabilities, the previous month prevalence of habitual cigarette smoking (6 or more cigarettes per day) decreased from about 14%e12% over the nine years. However, for persons with disabilities, the prevalence began at 20% in 2002, rose to a high of 22% in 2004, and then fell back to 20% once again. Consistently across all 9 years, persons with disabilities were much more likely than those without disabilities to smoke 6 or more cigarettes daily; the 2010 odds ratio was 1.83, with a 95% confidence interval of 1.68e1.99 ( p ! 0.001). Over time, the general trend for cigarette smoking at this level per day decreased significantly ( p ! 0.0001) for both populations, although the decrease was not as great among persons with disabilities. Alcohol was the only substance in this study for which estimates of the previous month prevalence of abuse (binge drinking) was lesser for persons with disabilities, ranging from 18% in the early years to 19% in later years, than that of persons without disabilities, which averaged about 21.5% in the study’s early years and reached its peak of 24% in 2009. Persons with disabilities were less likely than those without disabilities to admit having engaged in binge
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Table 1 Means of NSDUH regression analysis variables, 2002e2010 Variable a
Number of observations (unweighted) Dependent variables’ mean prevalence Any substance abuse in past month (prescription or illicit drugs, binge alcohol, or habitual cigarette smoking) Average of 6 cigarettes a day, past month Binge drinking in past month Marijuana use in past month Cocaine, crack, heroin, or meth, past month Powder cocaine use in past month Crack cocaine use in past month Powder or crack cocaine use in past month Heroin use in past month Methamphetamine use in past month Hallucinogens use in past month Ecstasy use in past month Any illicit drug use in past month (marijuana, powder or crack cocaine, heroin, methamphetamine, hallucinogens, or ecstasy) Alcohol abuse or any illicit drug use, past month Analgesics Oxycodone Tranquilizers Stimulants Sedatives Psychotherapeutics Independent variables’ mean frequencies Year dummy: 2002 Year dummy: 2003 Year dummy: 2004 Year dummy: 2005 Year dummy: 2006 Year dummy: 2007 Year dummy: 2008 Year dummy: 2009 Year dummy: 2010 Age 18e25 Age 26e34 Age 35 or more Male Female White Black/African American Hispanic Other race Education: Less than HS Education: HS graduate Education: some college Education: college graduate and higher Income: less than $10,000 per annum Income: $10,000e$20,000 per annum Income: $20,000e$30,000 per annum Income: $30,000e$40,000 per annum Income: $40,000e$50,000 per annum Income: $50,000e$75,000 per annum Income: more than $75,000 per annum Large urban area, 2004 or earlier Small urban area, 2004 or earlier Not an urban area, 2004 or earlier Large urban area, 2005 or later Small urban area, 2005 or later Not an urban area, 2005 or later a
Without disability
With disability
316,746
20,904
The maximum number of observations for the analysis. Some variables (e.g., oxycodone) have fewer.
0.355
0.403
0.156 0.248 0.061 0.010 0.008 0.002 0.008 0.001 0.002 0.004 0.002 0.065
0.276 0.179 0.067 0.020 0.016 0.009 0.016 0.003 0.003 0.003 0.001 0.077
0.266 0.018 0.002 0.007 0.004 0.001 0.025
0.214 0.028 0.003 0.013 0.005 0.003 0.037
0.108 0.109 0.110 0.111 0.113 0.113 0.112 0.113 0.113 0.153 0.166 0.681 0.483 0.517 0.704 0.105 0.129 0.062 0.150 0.309 0.257 0.284 0.058 0.107 0.114 0.118 0.117 0.186 0.301 0.148 0.108 0.070 0.354 0.276 0.043
0.088 0.087 0.091 0.095 0.097 0.108 0.137 0.142 0.155 0.081 0.102 0.817 0.464 0.536 0.593 0.219 0.139 0.049 0.325 0.370 0.208 0.097 0.211 0.274 0.152 0.109 0.082 0.091 0.081 0.101 0.088 0.077 0.334 0.333 0.067
R.E. Glazier and R.N. Kling / Disability and Health Journal 6 (2013) 107e115 Table 2 2010 odds ratios for differences between persons with and without disability Measure (abuse in past month) e 2010 results
Odds ratio Lower 95% CI Upper 95% CI p-value
Any substance abuse (prescription or Illicit drugs, Binge alcohol, or Habitual cigarette smoking) 1.280 Ave. 6 cigarettes/day in month 1.828 Binge drinking in past month 0.780 Marijuana use in past month 1.430 Cocaine, crack, heroin, or meth. 2.340 Powder cocaine 2.190 Crack cocaine 2.599 Powder or Crack cocaine 2.190 Heroin 4.715 Methamphetamine 2.630 Hallucinogens 0.924 Ecstasy 0.799 Any illicit drug (marijuana, powder or crack cocaine, heroin, methamphetamine, 1.480 hallucinogens, or ecstasy) Alcohol binge or any illicit drug 0.892 Analgesics 1.648 Oxycodone 3.035 Tranquilizers 2.038 Stimulants 1.638 Sedatives 3.008 Psychotherapeutics 1.625
drinking (5 or more drinks in one sitting) at least once in the previous month; the 2010 odds ratio was 0.78, with a 95% confidence level of 0.72 to 0.85 ( p ! 0.001). Note the more finely gradated scale of the X-axis, reflective of the lesser prevalence. There is a dramatic relative decline in the previous month prevalence of abuse of this group of four illegal drugs, with the trend for persons with disabilities very closely paralleling that for other persons. For persons without disabilities, the prevalence estimates fell rather steadily from 1.1% in 2002 to 0.4% in 2010. Comparatively, prevalence estimates for persons with disabilities declined to essentially the same degree over the period, from an initial high of 1.7% to 1.0%. Persons with disabilities were much more likely to admit to use of these four major illicit drugs than persons without disabilities, even as use declined in both populations; the 2010 odds ratio was 2.34, with a 95% confidence interval of 1.81 to 3.03 ( p ! 0.001). Both groups started the time period with very comparable estimated prevalence of marijuana use: 4.4% among persons without disabilities and 4.5% among persons with disabilities in 2002. However, over the nine-year span, persons with disabilities were much more likely to admit to having used marijuana in the previous month than persons without disabilities; the 2010 odds ratio was 1.43, with a 95% confidence interval of 1.26 to 1.63 ( p ! 0.001). There was a statistically significant upward trend overall ( p 5 0.0090) for marijuana use in both populations. However, the trajectory for persons with disabilities diverged from that of other persons ( p 5 0.0167) and showed a markedly steep path, ending at 6.6% in 2010 for a major (43%) difference in usage between the two populations in the last year of the study.
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1.194 1.682 0.716 1.258 1.805 1.632 1.683 1.632 2.581 1.622 0.619 0.439 1.308
1.371 1.987 0.849 1.625 3.033 2.937 4.012 2.937 8.612 4.266 1.380 1.455 1.675
!0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 !0.001 0.700 0.463 !0.001
0.821 1.350 1.760 1.595 1.186 1.817 1.402
0.969 2.010 5.233 2.606 2.262 4.978 1.884
0.007 !0.001 !0.001 !0.001 0.003 !0.001 !0.001
Among the individual illicit and prescription drugs we studied, the 2010 odds ratios for difference in selfreported use/abuse between persons with disabilities and those without disabilities were in some cases strikingly large and statistically significant (Reference Table 2 above.). For example (in descending order): Heroin, with an odds ratio of 4.72, 95% confidence interval of 2.58 to 8.61 ( p ! 0.001); Oxycodone, with an odds ratio of 3.01, 95% confidence interval of 1.76 to 5.23 ( p ! 0.001); Sedatives, with an odds ratio of 3.02, 95% confidence interval of 1.82 to 4.98 ( p O 0.001); Methamphetamine, with an odds ratio of 2.63, 95% confidence interval of 1.62 to 4.23 ( p ! 0.001); Crack cocaine, with an odds ratio of 2.60, 95% confidence interval of 1.68 to 4.01 ( p ! 0.001);
Fig. 1. Overall substance abuse e any drug abuse (prescription or illicit), smoking, or binge alcohol in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
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Powder Cocaine, with an odds ratio of 2.19, 95% confidence interval of 1.63 to 2.94 ( p ! 0.001); Tranquilizers, with an odds ratio of 2.04, 95% confidence interval of 1.60 to 2.61 ( p ! 0.001); Analgesics, with an odds ratio of 1.65, 95% confidence interval of 1.35 to 2.01 ( p ! .001); Stimulants, with an odds ratio of 1.64, 95% confidence interval of 1.19 to 2.28 ( p ! 0.001) and; Psychotherapeutics, with an odds ratio of 1.63, 95% confidence interval of 1.40 to 1.88 ( p ! 0.001).
Substance abuse of all types, including abuse of prescription drugs, is an even greater problem in the disability community than in the U.S. population at large. However, trends over the study time frame for both populations were pretty much parallel, with the notable exception of marijuana use (recreational or medical) and oxycodone abuse in the later years of the study; both marijuana use and oxycodone abuse accelerated sharply in the later years, and the prevalence among persons with disabilities diverged widely upward from that of other persons. It is notable that abuse of different classes of prescription drugs ranks prominently in the 2010 per-substance odds ratios between self-reports of persons with disabilities compared to that of other persons. Overall substance abuse (Please see Fig. 1.)dThe finding of significantly higher abuse prevalence (33% greater) among persons with disabilities is largely driven by their greater levels of habitual cigarette smoking, greater use of cocaine, and more frequent abuse of psychotherapeutic prescription drugs. There was no statistically significant time trend on this multi-factor measure, either for persons with disabilities or other persons. Cigarette smoking (Please see Fig. 2.)dSince WHO1 attributes the lion’s share of disease burden (19.2% of the roughly 23% total) to tobacco, the downward trend among persons without disabilities is somewhat encouraging, whereas the rather level trend in cigarette smoking by
persons with disabilities is not. This is a key substance of abuse, and in the world at large, it is on a steep trajectory as a major risk factor for greater morbidity and mortality.1 Some psychosocial research has attributed the higher level of smoking among persons with disabilities, and the greater prevalence of overall substance abuse, to a sense of personal ‘entitlement’ among persons with disabilities.2 In their research with Midwestern vocational rehabilitation consumers with significant disabilities, Li and Moore (2001) applied the concept of ‘secondary deviance’ in their examination of disability, ‘entitlement,’ and illicit drug use, concluding that: ‘‘.perceived discrimination and acceptance of disability play important roles in illicit drug use by persons with disabilities.14’’ They relate this phenomenon to the stigma, discriminatory labeling, and internalization of negative stereotypes experienced by other minority groups. Moore and Li measured the degree to which their survey sample felt that their stigmatized status ‘entitled’ them to engage in substance abuse by degree of agreement with the following survey statements: ‘‘1) People with disabilities have more reasons to use alcohol or other drugs than those without disabilities; 2) Because I have a disability, I sometimes feel that I have less to lose and more to gain from using alcohol or other drugs; and 3) People with disabilities already have many problems, so alcohol or drug use is not a big deal.’’ Alcohol abuseebinge drinking (Please see Fig. 3.)dThe lesser prevalence of binge drinking among persons with disabilities is a consistent and notable counter trend to the general pattern observed for other substances of abuse. Prevalence of binge drinking has remained essentially constant and parallel over this 9-year time frame for both populations. The National Health Interview Survey found a comparable alcohol abuse percentage (22.8) for the general civilian non-institutionalized population in 2009.15 The Behavioral Risk Factor Surveillance System (BRFSS) found a lower adult binge drinking prevalence, 15.2%, for 2009, probably due to the inclusion of persons over 65, who engage in this activity much less frequently. But the BRFSS also found an even lower prevalence (14.3%)
Fig. 2. Cigarette smoking e average 6 or more cigarettes per day in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Fig. 3. AlcoholeBinge drinking (5 or more drinks at one sitting) in previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Discussion
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among persons with disabilities. Other researchers comparing earlier binge drinking prevalence estimates from both the BRFSS and the NSDUH imply that the more confidential NSDUH interview process may account for that survey’s higher numbers.17 ‘‘Big Four’’ substance abuse (powder cocaine, crack, heroin, or methamphetamine) (Please see Fig. 4.)dAbuse of one of this group of four major illicit ‘street drugs’ is an indicator of serious drug addiction with criminal justice implications, not only because their very use is illegal, but because users often need to engage in other criminal behavioretheft or prostitutioneto support their habits. Note that, although the overall percentage admitting to use is much smaller for both populations than with other substances of abuse, the absolute numbers of users are strikingly large. In per-substance analyses, we found that the illicit drug trends for both groups were largely driven by the decrease in cocaine use (both powder and crack cocaine). Any marijuana use (Please see Fig. 5.)dIn both populations, there was an increase in previous month prevalence in the later years, an especially marked one for persons with disabilities. The trends for the two populations diverge dramatically in the later years, following medical marijuana legalization legislation in certain states (16 states þ D.C. by 2010), which might mean readier, perhaps subsidized medical marijuana availability for persons with disabilities. Strengths and limitations Among the great strengths of the NSDUH are its regular annual administration, the confidentiality provisions for self-reporting, and its great detail on the many forms of substance abuse, as well as its purposefully low 6th grade literacy level. For purposes of research focusing on the disability population, a significant limitation is its dearth of detail on the disability status of respondents. And, while the survey sample is selected to be nationally representative on various demographic dimensions, disability status is not a sampling factor. As noted earlier, the only question directly addressing disability consistently across the period
Fig. 4. ‘Big Four’ substance abuse (powder cocaine, crack, heroin, or methamphetamine) use in the previous month (regression-adjusted estimates from NSDUH, 2002e2010).
Fig. 5. Any marijuana use, including medical use in later years (regression-adjusted estimates from NSDUH, 2002e2010).
2002e2010 is whether the respondent is not working because of ‘work disability’.5 Our measure of disability is generally driven by work disability. This is in part a matter of practicality, as that is the measurement consistently available in the data across the time frame of the analysis. But this ‘limitation’ is also fortuitous, as the working age population constitutes an interesting group for policy study, and potentially for policy interventions related to the improvement of national economic productivity and the preservation of the Social Security Trust funds. Since having a work disability is often associated with very painful conditions like musculoskeletal disorders, our estimated odds ratios for those drugs, which are most prescribed for pain (analgesics, oxycodone) may be larger than if we had a differently defined disability population. Similarly, our estimated odds ratios for drugs which are most often prescribed for psychiatric conditions (psychotherapeutics) may be lower than if we had a differently defined disability population, e.g., if we had used the mental health markers introduced in the 2007 NSDUH. Overall, we may be generally understating the difference in substance abuse between those with and without disabilities, since it appears that NSDUH does not capture anyone whose disabilities are too burdensome to allow them to participate in the interview. Some of these non-respondents could have been those with the most significant physical and mental disabilities. Furthermore, the data reports make note of interviewer codes for ‘physically/mentally incompetent,’ classifications implemented at interviewer discretion,5 which may have introduced distortion through underinclusion of persons with severe disabilities; it is unclear in what ways this may have affected the findings of this study. Another complication arising from the NSDUH survey protocol is inaccessibility or potential loss of confidentiality for respondents with sensory disabilities because the instructions for self-administration of the survey are provided in an audio file inaccessible to persons who are deaf or severely hard of hearing, whereas the self-administered questions and response options on the laptop are provided visually, inaccessible to persons who are blind or have severe vision
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impairment. Persons with severe motor impairments likewise could have had their confidentiality compromised by being unable to register their self-reports without assistance from the interviewer or a fellow household member. Nonresponses or loss of confidentiality could also contribute to under-reporting of substance abuse. Furthermore, the exclusion of institutionalized persons is an understandable limitation that could have mixed effects on our findings, as these persons may have ready access to certain substances of abuse (e.g., cigarettes) and more restricted access to others (e.g., alcoholic beverages and prescription drugs that are administered in a carefully controlled manner). The survey’s inclusion, beginning in 2007, of mental health status measures opens up new avenues for research, e.g., utilizing NSDUH data to examine the complex relationship between different psychiatric disabilities and different forms of substance abuse, including trends over time. Similarly, the relationship between different nonpsychiatric disabilities and different types of substance abuse would become possible if the NSDUH were to include a comprehensive battery of disability questions. Access improvements in survey administration could improve the response rate among persons with disabilities and affect self-reported substance abuse in this population by ensuring improved confidentiality of responses.
Conclusions Over the period 2002e2010, the substance abuse trends for persons with disabilities, with a few notable exceptions, closely paralleled those for other persons in the U.S. residential population, but at a significantly higher level. The comprehensive substance abuse trend was level for both populations, but trends were down for: cigarette smoking, cocaine (both powder and crack), hallucinogens, and ecstasy for both persons with and without disabilities. The implication of these findings is that over time there are shifts in preference among specific substances of abuse that neither raise nor lower the overall abuse profile of either group. The previous month prevalence of substance abuse among persons with disabilities differed from that of other persons in significantly higher percentages of overall substance abuse, habitual cigarette smoking, use of the group of major illicit drugs, and marijuana use, with a significantly lower percentage of binge drinking. These differences were persistent across the time frame (2002e2010). There is good reason to believe (see study limitations above) that the underreporting of substance abuse is a more frequently occurring phenomenon among persons with disabilities than among the general population. Implications There seems to be no reason to question the face validity of the NSDUH self-reports of substance abuse, but only the
volume of them. Respondents have nothing to gain by privately admitting to behaviors generally regarded as socially deviant. Nor is there reason to believe that persons with disabilities have any reason to exaggerate their substance abuse behaviors. Therefore, it is apparent that overall substance abuse, while it is not normative behavior, is very common in the general population (1 in 3 persons) and even more common among persons with disabilities (2 in 5 persons). Examination of the substance-specific trends for the disability community can inform differential messaging and appropriate, accessible substance abuse prevention programs for persons with disabilities. Given the findings reported herein, the multitude of debilitating effects of cigarette smoking, and both the direct health care costs and the lost productivity implications of smoking, combined with the relatively low cost of tobacco cessation programs, the importance of promoting smoking cessation through culturally competent messaging via accessible media cannot be overemphasized. Other major substance abuse prevention priority targets for appropriate messaging to the disability community via accessible media include: 1) dangers of heroin use and inherent addiction (including the HIV/AIDS hazard from shared needles) and the benefits of methadone treatment; 2) the powerful addiction potential of oxycodone in the various forms in which it is abused (ingestion, inhalation, IV injection) and treatment and recovery options; 3) the problems associated with use of highly addictive methamphetamine and cocaine (powder and crack) and treatment/rehabilitation options; and 4) preventing abuse of prescription drugs to which many persons with disabilities have legitimate accesse sedatives, tranquilizers, analgesics (painkillers), stimulants, and psychotherapeuticsein the form both of self- abuse through misuse, overuse, super-dose, as well as facilitating abuse by others through inattention to missing medications ‘borrowed’ by friends or family, or intentional diversion of prescription medications into street trafficking for profit. Similarly, the trends document the increasing need for accessible substance abuse treatment facilities and programs, and appropriate treatment and recovery services that accurately target persons with disabilities’ different forms and patterns of abuse. The woeful inadequacy of accessible SA treatment facilities and programs in the U.S. was recently documented in a nationally representative survey: ‘‘Most responding facilities self-reported a variety of barriers to physical accessibility, as well as the lack of services and physical accommodations for persons with sensory limitations. Such widespread inaccessibility may be a factor that promotes the low representation of persons with disabilities in the treatment population.18’’ Extrapolating the prevalence we found to the U.S. Census 2010 estimate that there were 19,048,426 civilian non-institutionalized persons with disabilities,19 if all such persons with any form of substance abuse (40.3%) had sought treatment, the national caseload for only persons
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with disabilities would have been 7,676,516. If, more conservatively, only persons who reported that they used illicit drugs or abused alcohol in 2010 (21.4%) applied for alcohol or drug abuse treatment services, that disability caseload would have been 4,076,363. For some substances of abuse, there are day treatment programs, new detoxification protocols, new pharmaceuticals (e.g., Naltrexone, introduced over a decade ago for treatment of alcoholism and opioid dependence), 12-step programs, alternative therapies like acupuncture, and other options short of inpatient treatment. Peer support and peer counseling can be crucially important in the treatment and recovery process. We suppose that many persons with disabilities who are in recovery might have difficulty finding true peers with whom to share their experience and provide needed social support, other persons with the same type of disability and the same substance abuse issues. The message of hope for recovery through the various available substance abuse treatment modalities is something all affected persons need to hear. Persons with disabilities, their families, and friends must be afforded the same opportunity.
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Acknowledgments Credit is due to the Substance Abuse and Mental Health Services Administration (SAMHSA) of the U.S. Department of Health and Human Services for its long-term commitment to sponsoring the National Survey on Drug Use and Health (NSDUH) and its predecessor, the National Household Survey on Drug Abuse (NHSDA). References 1. World Health Organization. World Health Report 2002: Reducing Risks, Promoting Healthy Life, http://www.who.int/whr/2002/en/ whr02_en.pdf; 2002. Accessed 29.06.12. 2. Li L, Moore D. Page 5 in: Disability and illicit drug use: an application of labeling theory. Deviant Behavior. 2001;22:1e21. 3. Alcoholism & Drug Abuse Weekly; August 15, 2005. p. 3. 4. Office on Disability, U.S. Department of Health and Human Services (Undated). Substance abuse and disability: a companion to chapter 26 of healthy people 2010. http://www.hhs.gov/od/about/fact_sheets/ substanceabusech26.html; Accessed 22.03.12. 5. Office of Applied Statistics, Substance Abuse and Mental Health Services Administration (SAMHSA). National Survey on Drug Use
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