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Impact of Work Therapy on Health Status Among Homeless, Substance-Dependent Veterans
A Randomized Controlled Trial
T. Michael Kashner, PhD, JD;
Robert Rosenheck, MD;
Anthony Brian Campinell, MEd;
Alina Surís, PhD;
Randy Crandall, MS;
Nancy J. Garfield, PhD;
Paul Lapuc, PhD;
Karen Pyrcz, MS;
Thomas Soyka, MS;
Annie Wicker, BS;
and the CWT Study Team
Arch Gen Psychiatry. 2002;59:938-944.
ABSTRACT
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Background Little is known about the health outcomes of clinician-supervised, performance-based,
abstinence-contingent therapeutic work programs on homeless persons with addiction
disorders. This study examined the effect of the Department of Veterans Affairs
compensated work therapy program (CWT) on nonvocational outcomes. With mandatory
urine screenings and adherence to addiction treatment schedules, CWT provided
work opportunities (wages, hours, and responsibilities) with jobs created
from Veterans Affairs contracts competitively obtained from private industry.
Methods Homeless, substance-dependent veterans (N = 142) from 4 Department of
Veterans Affairs medical centers were randomized, assessed at baseline, and
reassessed at 3-month intervals for 1 year. Both CWT and control groups had
access to comprehensive rehabilitation, addictions, psychiatric, and medical
services. Data were analyzed to determine an immediate CWT effect after treatment
and rates of change during 1 year.
Results Compared with control subjects, patients in the CWT program were more
likely to (1) initiate outpatient addictions treatment, (2) experience fewer
drug and alcohol problems, (3) report fewer physical symptoms related to substance
use, (4) avoid further loss of physical functioning, and (5) have fewer episodes
of homelessness and incarceration. No effect on psychiatric outcomes was found.
Conclusion Work therapy can enhance nonvocational outcomes of addiction treatment
for homeless persons, although long-term gains remain unknown.
INTRODUCTION
MENTAL HEALTH professionals often refer clients to clinical programs
where the primary goal is competitive employment. These programs of vocational
rehabilitation, sheltered workshops, job clubs, and transitional and supported
employment have shown varying degrees of success in helping the mentally ill
attain employment.1-5
However, the relationship between structured work and nonvocational health
outcomes remains inconclusive.
In contrast, economists consider productive work as an outcome of a
healthy labor force.6 Epidemiologists emphasize
work-related illnesses,7 hazards,8-9
stresses,10-11 and adverse health
behaviors.12 Public health research finds retirement
often leading to poorer physical functioning,13-15
somatic complaints,16 and fatal heart attacks,17 although it is unclear whether retirement resulted
in or from poor health. What is not known is whether structured work can change
health behaviors and, thus, health status.
The current study focuses on the Department of Veterans Affairs (VA)
compensated work therapy (CWT) program, a clinician-supervised, abstinence-contingent,
performance-based work program for homeless persons. The CWT program offers
pay rewards but requires random drug testing and adherence to a schedule of
outpatient addiction services determined to be clinically appropriate for
each client. The program's clinical setting ensures that the link between
work performance (productivity and presentation) and health behaviors (sobriety
and use of addiction services) to job rewards (wages, hours, and responsibilities)
are not undermined by the vicissitudes of labor markets. The study focused
on homeless persons who lack regular employment and structured environments.
Study outcomes included substance dependence behaviors (substance consumption
and use of addictions treatment services), health outcomes (addiction-related
physical symptoms, psychiatric symptoms, and health functioning), and other
aspects of quality of life (rates of incarceration and homelessness). The
study was set at VA medical centers where all clients had access to comprehensive
health services, including addictions treatment and vocational rehabilitation.
Access to care did not depend on employment status.
SUBJECTS AND METHODS
SUBJECT SELECTION
Subjects were recruited from homeless centers and addiction units at
4 VA medical centers located in Bedford, Mass; Northampton, Mass; Topeka,
Kan; and St Cloud, Minn. Qualifying subjects (1) were eligible for VA care,
(2) were homeless at intake, (3) satisfied DSM-III-R
criteria for substance dependence or abuse,18
and (4) were willing to enter a therapeutic work program. For this study,
homeless persons have "a primary nighttime residence that is a supervised
publicly or privately operated shelter designed to provide temporary living
accommodations, an institution that provides a temporary residence for individuals
intended to be institutionalized, or a public or private place not designed
for, or ordinarily used as, a regular sleeping accommodation for human beings"
(McKinney Act, 42 USC 11302). Excluded patients were those (1) institutionalized
at intake, (2) mentally or physically unable to work in the opinion of the
CWT admitting clinician, (3) diagnosed with a terminal illness, (4) planning
to leave the study service area within 1 year, or (5) unresponsive at the
intake interview.
INTERVENTION
First introduced in 1957 (38 USC 1718), the VA CWT programs19 teach work discipline with abstinent-contingent, performance-based
work for pay in staff-supervised, structured settings. As administered at
the 4 study sites between July 1, 1994, and March 31, 1997, CWT offered work
opportunities (continued employment, higher wages, hours, promotion, and responsibility)
based on client work performance (productivity, reliability, presentation,
and punctuality) and health behavior (sobriety and use of recommended addiction
services) as judged by CWT clinicians through client observation, random drug
screenings, and chart reviews. The CWT combined elements of supported employment
(nontrivial wages paid from revenues earned from private sector contracts)
and stepwise programs (clinician supervision and VA workshops). Consequences
for inappropriate behaviors (positive drug screenings) varied from a reprimand
to program dismissal and loss of CWT employment. Unfettered by informal organizations,
appellate bureaucracies, and labor regulations, clinician managers were free
to protect the integrity of work incentives and make judgments in the client's
best interest. Control patients were not enrolled in CWT for at least the
1-year follow-up, although both subjects who received CWT and control subjects
had full access to VA comprehensive medical, mental, addictions, and vocational
rehabilitation services, including job-seeking skills and support, job documentation
and interviewing techniques, and career counseling and assessment.
We hypothesized that the mandatory addiction treatment and drug screening
protocols in CWT, among other factors, would have an immediate impact on addiction
status as assessed by patient use of drugs and alcohol, and secondarily on
patient use of addiction services and prevalence of substance use–related
symptoms. We also hypothesized that subjects in the CWT group would gradually
experience better psychiatric and medical status during the 1-year follow-up
after CWT began.
RANDOMIZATION
Research assistants at each of the 4 study sites admitted patients,
checked eligibility, administered baseline questionnaires, and then called
a national coordinator (A.W.) in Dallas, Tex, to receive a patient identification
number. Once the subject was assigned to a number, the coordinator revealed
treatment assignment by opening, in sequence, sealed envelopes that had been
addressed to both site and patient identification number. The enclosed assignments
were based on random numbers generated by an SPSS program (SPSS Inc, Chicago,
Ill). To attract subjects, a sampling ratio of 1 (control) to 4 (subject in
CWT) was adopted. Subjects randomized to CWT were offered employment as soon
as a CWT-sponsored job became available, usually within 6 days. After the
baseline interview, neither patient nor assessors were blinded to study assignments.
MEASUREMENTS
Data came from face-to-face interviews conducted at baseline and at
3-month intervals for 1 year by trained interviewers under supervision of
master's- or doctorate-level prepared social workers and psychologists. Information
was verified by VA computerized file extracts and patient chart reviews. To
ensure reliability of data collection, interviewers received group training,
participated in routine conference calls, and were tested by rating prerecorded
taped interviews.
As the primary measure, addiction status was determined by the Addiction
Severity Index (ASI),20-22
summarizing drug and alcohol use problems into composite scores ranging from
0 to 1, with higher scores indicating more problems. Administered under confidential
circumstances, these measures have been shown to be valid.23
As confirmatory measures of outcome, addiction care–seeking behavior
was represented by a dichotomous variable that assumed a value of 1 if the
patient had obtained at least 1 outpatient addiction visit during a 3-month
period before each follow-up interview, and 0 otherwise. Substance use–related
physi cal problems were measured as a simple count of 11 symptoms that included
the presence or absence of seizures, delirium tremens, or memory trouble;
seeing or hearing things not there after cutting down on substance use; liver
disease; hepatitis or yellow jaundice; vomited blood or other stomach troubles;
tingling or numbness in feet; inflammation of pancreas or pancreatitis; drug
overdose; subacute bacterial endocarditis; cellulitis or other infections
due to intravenous drug use; and continued use when aware that consumption
may exacerbate serious physical illness.
Exploratory outcomes included psychiatric status assessed by a normalized
global Brief Symptom Inventory,24-25
the ASI Psychiatric Status, and the Mental and Social Functioning components
of the 36-Item Short Form Health Survey from the Medical Outcomes Study (SF-36).26-27 Medical status was assessed with the
Physical Functioning component of the SF-36 and the Medical Status component
of the ASI. Other measures included presence or absence of episodes of criminal
justice incarceration and homeless nights during the 3 months before each
interview.
The cost of inpatient (outpatient) care was calculated in 3-month intervals
by multiplying the number of days (visits) by a cost per day (per visit) and
summed over all respective bed sections (clinic stops). Costs were calculated
for medicine, psychiatry, and addiction and rehabilitation services. Unit
costs were based on median cost (1997 US dollars) for VA medical centers.
Data came from VA's cost files that include costs for professional time, supplies,
indirect administrative support and building maintenance, and depreciation
for equipment and buildings.28 Separate estimates
were calculated for medical, psychiatric, and addiction and rehabilitation
services.
STATISTICAL ANALYSES
Two-tailed  2 (discrete) and t
(continuous) tests compared group differences at baseline. Longitudinal outcome
data were analyzed by hierarchical regressions with the use of HLM/3L software29 to compute outcome differences between CWT and control
groups as a percentage of baseline scores (continuous measures) and an odds
ratio (dichotomous measures).
Tracking homeless patients necessitated the use of parametric statistics
to account for missing observations and variable intervals between follow-up
interviews, discussed in clinical trials generally30
and mental health specifically.31-32
With these approaches, time of observation enters as an explanatory variable
to determine whether measured outcomes change with time.33-34
Clinical programs are evaluated by detecting whether differences between treated
and control subjects "grow" over time,35-37
although estimates are unbiased only to the extent that the occurrence of
missing values and length of intervals between follow-ups are uncorrelated
with treatment assignment. The approach permits one to adjust for patient
use of other services as time-dependent covariates.
Traditional parametric approaches determine treatment effects by detecting
whether differences in outcomes between treated and control patients grow
with time. These growth strategies may not describe programs that focus on
behavior (eg, addictions). Here, program benefits may mature immediately after
treatment begins, only to diminish with time because (1) efficacy "wears off,"
(2) efficacious alternatives help control clients "catch up," (3) the intervention
only enhances the speed of recovery, or (4) the intervention postpones inevitable
outcomes of an intractable disorder. Thus, we estimated immediate and growth-rate
effects by means of a declining-effects model (T.M.K., Thomas J. Carmody,
PhD, Trish Suppes, MD, PhD, A. John Rush, MD, M. Lynn Crismon, PharmD, Alexander
L. Miller, MD, Marchia Toprac, PhD, and Madhukar Trivedi, MD, unpublished
data, August 2001):
ysit =  0
+ 1Isi
+ 20Zt + 21ZtIsi + 30t + 31tIsi + 4csit +  s + usi + vsit,
where ysit is the outcome assessed
for patient i at site s (s = 1, 2, . . . 4) at t quarters (3 months)
past baseline (t = 0). To evaluate CWT, the "intent-to-treat"
variable Isi assigns a value of 1 for
patients randomized to CWT and 0 if assigned to the control group. Zt is a dummy variable that assumes a value of 1 for t>0, and 0 otherwise.
The variable csit is use of care during 3 months before t, including psychiatric
care (psychiatric status outcomes), medical care (medical outcomes), and addiction
and rehabilitation services (addiction status). The use of care covariate
was excluded when use of addiction services was the dependent variable. The usi and vsit are random
variates representing each patient and each assessment, assumed to be independent
and normally distributed with 0 mean and constant variance during the 1-year
follow-up.
As with traditional models, the growth-rate effect (31)
describes how outcome differences between CWT and controls grow, or decline,
with time. The immediate effect (21) describes how a lump-sum
difference in outcomes between CWT and control subjects may occur initially
after active CWT. Thus, outcome difference between CWT and control subjects
for t>0 equals 21 + 31t. Other parameters are the average starting
value for control subjects (0); difference between CWT and
control groups at baseline (t = 0) (1); initial "lump-sum" change in outcomes for control subjects (20); growth rate in outcomes for control subjects (30);
use of care main effect (4); and fixed effects reflecting
site-specific differences in average outcomes (s), with s = 0 for s = 1, the reference
site.
The equation simplifies to a growth model when 20 =
0 and 21 = 0 and can be modified to a logistic regression
for dichotomous outcome variables.
RESULTS
Data collection began July 19, 1994, with recruitment ending March 22,
1996, and follow-up assessments ending April 1, 1997. Figure 1 describes the progress through the trial of the original
1090 subjects who had been discharged from VA addiction programs and whose
names were referred for study. The large number of no-shows and patients unable
to be located reflects difficulties inherent in studying homeless populations.
The final sample (N = 142) was evenly distributed among the 4 sites (37%,
22%, 21%, and 20%) and included 22 (15%) who completed 2 follow-ups; 21 (15%),
3 follow-ups; and 99 (70%), 4 follow-ups.
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Patient progress through the trial. VA indicates Veterans Affairs;
CWT, compensated work therapy.
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The final sample did not differ from the 201 excluded eligible subjects
(181 nonconsenting and 20 lost to follow-up) with respect to demographic characteristics
(mean age, 43.1 vs 41.9 years, t = 1.44, P<.15; African American, 26% vs 25%, t
= 0.22, P<.83; years of education, 12.7 vs 12.6, t = 0.21, P<.84), cost of VA
care during the year before baseline ($26 199 vs $25 133, t = 0.41, P<.68), and health
status (ASI for alcohol problems, 0.36 vs 0.36, t
= 0.03, P<.98; ASI for drug problems, 0.11 vs
0.12, t = 1.22, P<.23;
physical symptoms relating to substance use, 3.52 vs 3.53, t = 0.04, P<.97; ASI psychiatric status,
0.39 vs 0.38, t = 0.25, P<.81;
Brief Symptom Inventory global status, 0.002 vs 0.001, t = 0.16, P<.87; SF-36 Mental Functioning,
50.2 vs 50.6, t = 0.16, P<.87;
SF-36 Social Functioning, 58.9 vs 57.8, t = 0.30, P<.77; ASI edical Status, 0.35 vs 0.29, t = 1.39, P<.17; and SF-36 Physical Functioning,
85.9 vs 84.2, t = 0.77, P<.44).
Despite a 12% loss to follow-up, Table
1 shows no statistically significant difference between the CWT
(n = 111) and control (n = 31) groups for demographic characteristics and
outcome measures assessed at baseline. During the year after baseline, both
CWT and control groups had extensive use of health services, including psychiatric
and rehabilitation care, although differences reached statistical significance
only in inpatient medicine days and outpatient addiction visits.
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Table 1. Patient Characteristics at Baseline and 1 Year*
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Subjects assigned to CWT received a job within a median 6 days after
baseline and worked a mean of 393 hours (SD, 474 hours) at an average wage
of $4.04/h (SD, $1.80/h; range, $0.50/h to $10.75/h). Of hours worked, 58%
were unskilled, 22% semiskilled, 16% skilled labor, and 4% clerical, sales,
or technical related. Working subjects were screened for substance use an
average 8.6 times (SD, 10.7), or approximately once every 20 work days. Among
those tested, 44% had at least 1 positive screening, with 15% of screenings
testing positive.
Utilization covariates (measured in dollars) were significant predictors
of patient outcomes for ASI drug (4 = 0.003, t393 = 2.25, P<.02) and alcohol
(4 = 0.008, t393 = 2.31, P<.02) use problems, psychiatric status (4 = 0.011, t393 = 2.18, P<.03), number of substance use– related physical symptoms
(4 = 0.18, t393 = 3.85, P<.001), and SF-36 Mental Functioning (4 = -1.07, t393 = 1.97, P<.049) and Social Functioning (4 = -1.88, t393 = 2.53, P<.01).
The CWT immediate and growth-rate effects are presented in Table 2 for each of the 12 outcome measures
as a percentage of average baseline scores (continuous) or as odds ratios
(dichotomous). Consistent with expectations, CWT clients were initially 2.7
times more likely to use addiction treatment than their control counterparts.
After adjustment for greater use of addiction treatment with ±SE, patients
who received CWT experienced immediate reductions in drug (-44.7% ±
12.8%) and alcohol (-45.4% ± 9.4%) use problems, and the number
of substance use–related physical symptoms (-64.4% ± 8.0%).
These immediate differences tended to decline with time, although such a "catch-up"
pattern was statistically significant for only the number of substance use–related
physical symptoms. Here, group differences declined by 17.0% ± 5.1%
per quarter as control subjects, unlike their CWT counterparts, experienced
a reduction in symptoms during follow-up by an average of -19.2% ±
4.4% per quarter.
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Table 2. Adjusted CWT Immediate and Growth-Rate Effects, by Outcome*
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There were no significant difference in psychiatric status between the
CWT and control groups on any of the 4 outcome measures. On the other hand,
differences between CWT and control groups tended to grow during follow-up
by -24.4% ± 8.7% per quarter on the basis of ASI Medical Status
and 6.9% ± 2.0% per quarter on the basis of SF-36 Physical Functioning.
However, these gains were due primarily to declining function among control
subjects (ASI Medical Status, 23.9% ± 7.6% per quarter; SF-36 Physical
Functioning, -6.2% ± 1.8% per quarter) rather than from improved
functioning among subjects in the CWT group (ASI Medical Status, -0.4%
± 11.5% per quarter; SF-36 Physical Functioning, 0.6% ± 2.7%
per quarter). Finally, patients in the CWT group were initially 30% and 10%
as likely to report an episode of incarceration and homelessness, respectively,
as their control counterparts.
COMMENT
In this randomized, controlled trial, we evaluated a clinician-supervised,
performance-based work program that tied paid work opportunities (hours, wages,
and responsibilities) to performance (productivity, punctuality, and reliability)
and health behaviors (sobriety and use of addiction services). Among homeless,
substance-dependent persons with expressed desires to work, CWT was associated
with greater use of addiction services. Even after adjustment for use of health
and rehabilitative services, these data suggest that CWT clients experienced
fewer problems associated with substance use and fewer episodes of homelessness
and incarceration. The CWT clients also did not report the same decline in
medical status and physical functioning exhibited by control subjects. However,
no work effect on psychiatric status was detected. These differences are remarkable
given that both groups had extensive use of medical, psychiatric, addictions,
and rehabilitation services from local VA medical centers. However, patients
in the CWT group reported generally more inpatient days and outpatient visits,
suggesting that these outcomes may come at the price of higher health care
costs.
These findings are consistent with those of the Milby et al study40 of substance-abusing homeless persons, in which abstinent
contingent work therapy was found to be associated with 36% fewer positive
cocaine toxicologic tests within 2 months of beginning treatment. These results
are also consistent with the findings of Bell et al41-42
that paid vs unpaid work at VA medical facilities was associated with symptom
reductions for patients with schizophrenia or schizoaffective disorders, and
with Rosenheck and Seibyl's43 observational
study that showed that receiving care at a residential support facility offering
therapeutic work, but requiring responsible behavior, was associated with
substance abuse, but not psychiatric symptoms. These results contrast with
findings from assertive community treatment programs for homeless substance
abusers that failed to find high rates of abstinence,44
and from supported employment in competitive work environments that failed
to find symptom reductions.33, 45
However, these latter studies focused on severe mental illness.
It is unknown which CWT elements may have contributed to program outcomes:
structured work, pay incentives for mandatory substance screenings and adherence
to addiction treatment schedules, clinician supervision, and improved access
to care. Comparing other studies, Ames and Janes46
found that boring, stressful, and isolating work can in fact contribute to
substance use behaviors, while alcoholic subjects who returned to work were
likely to remain sober, but only when the job discouraged drinking behaviors
and offered structured supervision.47-48
A recent econometric analysis (2-stage least-squares adjusting for self-selection)
of national survey data (1991 and 1993 National Health Interview Surveys)
suggested that workplace bans were associated with a 5–percentage point
reduction in smoking prevalence and a 10% reduction in daily consumption among
smokers, and accounted for all of the explained variance in smoking reduction
among workers relative to nonworkers.49 Additional
study is needed to untangle how program elements contribute to outcomes. With
the success of supported employment programs, however, future studies should
consider how outcomes vary between clinical and competitive employment settings.
There are study limitations. Findings were limited to a VA setting,
142 subjects, 1 year of follow-up, a low consent rate (47%), and a 1:4 sampling
ratio that further limited statistical power. Outcomes measures were based
on patient self-reports, although between-group biases may be small. First,
CWT drug screenings averaged once every 20 days, so that hiding information
from independent research teams may have had little perceived consequence
on work opportunities. Second, control subjects wanting to enter CWT after
completing the study had incentives to also underreport symptoms. Third, reduced
substance consumption was consistent with patterns observed for other outcomes,
including use of addiction services, substance use–related symptoms,
medical status, and other measures.
Biases associated with nonrandomly occurring missing data and variable
intervals between repeated measures may also be small. Compared with control
subjects, CWT clients had a comparable number of observations (3.6 vs 3.8; t = 1.44, P<.15) and time between
observations (1.5 vs 1.4 quarters; t = 1.26, P<.21). Regression to the mean bias either works against
study findings (symptom counts) or is small compared with estimated effect
size (drug and alcohol use problems).
In summary, the VA's CWT program was associated with better addiction
status and with fewer episodes of homelessness and incarceration, and appears
to prevent further deterioration in medical status and physical functioning.
More research is needed to assess long-term impacts and to determine the active
program ingredients contributing to outcomes.
AUTHOR INFORMATION
Submitted for publication December 3, 1999; final revision received
December 14, 2001; accepted December 20, 2001.
This study was supported in part by the Department of Veterans Affairs,
Health Services Research and Development Service grant IIR 92-043 and Research
Career Scientist Award 92-403, Washington, DC, and by grant 5-R24-MH53799
from the National Institute of Mental Health, Bethesda, Md.
We thank Mary Kashner, Pauline Salyer, Perry Lambird, MD, Mona Sue Lambird,
JD, George Moore, Robert D. Fowler, MD, Stephen Berman, MSW, and A. John Rush,
MD, for their special contributions in advancing this study.
The opinions expressed herein are those of the authors and do not necessarily
reflect the views of supporting agencies and sponsors.
Corresponding author and reprints: T. Michael Kashner, PhD, JD, Department
of Psychiatry, The University of Texas Southwestern Medical Center at Dallas,
5323 Harry Hines Blvd, Dallas, TX 75390-9086.
From the Department of Veterans Affairs Medical Centers at Dallas,
Tex (Drs Kashner and Surís and Ms Wicker), West Haven, Conn (Dr Rosenheck),
Bedford, Mass (Mr Campinell and Ms Pyrcz), St Cloud, Minn (Mr Soyka), Topeka,
Kan (Mr Crandall and Dr Garfield), and Northampton, Mass (Dr Lapuc); the Department
of Psychiatry, The University of Texas Southwestern Medical Center at Dallas
(Drs Kashner and Surís and Ms Wicker); and the Department of Psychiatry,
Yale University (Dr Rosenheck).
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