Download Effects of Long-Term, Medically Supervised, Drug

SUPPLEMENT ARTICLE
Effects of Long-Term, Medically Supervised,
Drug-Free Treatment and Methadone Maintenance
Treatment on Drug Users’ Emergency Department
Use and Hospitalization
Barbara J. Turner,1 Christine Laine,2 Chuya P. Yang,1 and Walter W. Hauck3
1
Division of General Internal Medicine, Department of Medicine, University of Pennsylvania School of Medicine, and 2Division of Internal
Medicine, Center for Research in Medical Education and Health Care, and 3Division of Clinical Pharmacology, Jefferson Medical College,
Thomas Jefferson University, Philadelphia, Pennsylvania
We examined the effect of drug treatment in 1996 on repeated (⭓2) emergency department visits and hospitalization in 1997 in a cohort of New York State Medicaid–enrolled human immunodeficiency virus (HIV)–
positive and HIV-negative drug users. In HIV-positive drug users, the adjusted odds of repeated emergency
department visits were increased for those receiving no long-term treatment (odds ratio [OR], 1.65; 95%
confidence interval [CI], 1.04–2.75), whereas the adjusted odds for those receiving methadone treatment and
those receiving drug-free treatment for ⭓6 months did not differ. The adjusted odds of hospitalization in the
HIV-positive group were higher for those receiving long-term methadone treatment (OR, 1.69; 95% CI, 1.14–
2.55) and for those receiving no long-term treatment (OR, 1.91; 95% CI, 1.29–2.88), compared with those
receiving drug-free treatment. In the HIV-negative group, these associations were similar but weaker. For both
HIV-positive and HIV-negative drug users, long-term drug-free treatment was at least as effective as longterm methadone treatment in reducing use of services indicative of poorer access to care and/or poorer health.
Drug abuse is increasingly understood to be a chronic
health condition necessitating long-term treatment [1].
Long-term treatment for injection drug users has been
shown to reduce the risk of HIV seroconversion [2]
and death [3]. A National Institutes of Health Expert
Consensus Report reaffirmed the value of long-term
methadone treatment as an effective intervention for
opiate dependence [4]. Yet, it is less clear whether medically supervised treatment without methadone or other
pharmacological agents (i.e., drug-free programs) has
similar favorable effects on patients’ outcomes. Because
many patients in drug-free treatment abuse nonopiate
drugs, such as cocaine, an assessment of the benefits
of this care has relevance to regions of the world where
cocaine abuse is prevalent. Both HIV-positive and HIVnegative drug users have drug-related medical and
other conditions that prompt heavy use of emergency
departments (EDs) and hospitals [5, 6]. This study
probes the benefits of these 2 dominant forms of nonresidential drug treatment with regard to 2 types of
services indicative of clinical instability: repeated ED
utilization and hospitalization.
Financial support: National Institutes of Health (grant DA-11606).
The opinions of the authors do not necessarily reflect those of the New York
State Department of Health.
Reprints or correspondence: Dr. Barbara J. Turner, University of Pennsylvania,
1123 Blockley Hall/6021, 423 Guardian Dr., Philadelphia, PA 19104 (bturner@
mail.med.upenn.edu).
Clinical Infectious Diseases 2003; 37(Suppl 5):S457–63
2003by the Infectious Diseases Society of America. All rights reserved.
1058-4838/2003/3712S5-0023$15.00
METHODS
We conducted a retrospective cohort study of drug
users enrolled in the New York State Medicaid program
from federal fiscal year 1996 through 1997. Data were
from longitudinally linked claims for all ambulatory
Drug Treatment and Hospital Use among IDUs • CID 2003:37 (Suppl 5) • S457
Table 1.
Characteristics of a cohort of HIV-positive and HIV-negative drug users in New York State in 1996.
No. (%) of study subjects, by long-term treatment received and HIV status
Methadone
Variable
Drug-free
⫺
None
HIV
(n p 4569)
HIV
(n p 11,370)
HIV
(n p 126)
HIV
(n p 1154)
HIV
(n p 6861)
HIV⫺
(n p 34,163)
39.2
41.9
48.4
55.2
38.8
43.1
+
+
⫺
+
Demographic
Female
Age in years
!30
4.2
7.2
15.1
19.8
10.1
24.1
30–39
37.6
34.7
50.0
45.6
46.2
42.3
40–49
49.8
47.0
29.4
25.2
36.9
25.7
8.4
11.2
5.6
9.5
6.8
7.9
92.1
86.6
81.8
64.3
86.8
59.4
⭓50
Area of residence
New York City
New York City suburbs
5.3
7.2
8.7
9.4
4.3
8.8
Upstate urban
2.0
4.2
2.4
17.3
6.1
17.9
Small city
0.2
0.8
1.6
3.9
1.3
5.9
Rural
0.04
1.3
5.6
5.1
1.6
8.0
17.4
15.9
16.6
18.8
16.6
3.9
Clinical
Chronic diseases other than
HIV infection
1
17.8
2
4.3
4.2
2.4
2.3
4.8
⭓3
1.1
0.9
0
0.4
1.1
1.2
18.2
15.4
16.7
20.7
25.5
32.7
Regular source of medical care
49.4
44.7
58.7
57.4
53.2
55.1
HIV specialty care
68.9
NA
61.1
NA
57.4
NA
Mental health disorder
Health care
NOTE.
NA, not applicable.
medical services from physicians and clinics as well as substance
abuse services covered by the Medicaid program. These files
contain information on inpatient, pharmacy, home health care,
case management, and laboratory diagnostic services.
We identified Medicaid claims associated with illicit drug use,
HIV infection, and AIDS by means of previously reported and
evaluated algorithms [7–9]. The operating characteristics of the
algorithms for finding drug users and HIV cases are very good
to excellent [6]. We identified drug users who were aged 13–60
years in 1996 and enrolled in Medicaid for at least 10 months
in 1996 (n p 78,943). Of these drug users, 77,618 had ⭓1 outpatient visit(s) in 1996 (required for analysis of patterns of care),
59,104 were enrolled in Medicaid for ⭓10 months in 1997, but
demographic data were available for 59,092. After excluding
women who were pregnant in 1997, we studied a total of 58,243
persons.
Study-dependent variables were ⭓1 hospitalization in federal
fiscal year 1997 and ⭓2 ED visits during that year. Hospitalizations were determined from Medicaid claims for inpatient
stays of ⭓1 day. We considered repeated ED visits, as evidenced
S458 • CID 2003:37 (Suppl 5) • Turner et al.
by claims on separate days, as our outcome, because 1 visit
does not indicate excessive reliance on the ED for care [10].
ED claims made before a hospitalization were not included.
By use of Medicaid claims in 1996, we classified drug users
as having either long-term ambulatory drug treatment from a
single methadone program or a medically supervised drug-free
treatment program (as defined in New York State regulations,
title 12 NYCRR, part 822, mental hygiene law, chemical dependence outpatient services) for at least 6 contiguous calendar
months in 1996 or neither form of long-term drug treatment.
We did not consider detoxification, residential, and non–medically supervised ambulatory programs in this analysis so as to
focus on the effects of medically supervised outpatient care.
We applied a 6-month minimum criterion for the duration
of drug treatment on the basis of evidence from studies of methadone and cocaine abuse treatment [11, 12]. Our final drug
treatment categories included the following: long-term methadone maintenance treatment, long-term medically supervised
drug treatment, and no long-term drug treatment. Some persons
who received residential drug treatment may be included in the
Table 2. Unadjusted association of health care delivery variables repeated emergency department (ED) use and hospitalization in 1997 for a cohort of HIV-positive and HIV-negative
drug users in New York State.
Percentage of study subjects,
by repeated ED use, hospitalization, and HIV status
Repeated ED use
Hospitalization
HIV
(n p 11,556)
HIV
(n p 46,687)
HIV+
(n p 11,556)
HIV⫺
(n p 46,687)
25.0
22.1
55.6
37.5
Drug-free
16.7b
16.2b
34.1b
23.9b
Methadone
18.9
13.2
47.8
24.9
None
29.2
25.3
61.3
42.1
No
25.6
18.6
56.5
35.0
Yes
24.5
25.3
54.8
39.7
No
25.5
NA
58.8b
NA
Yes
24.7
NA
53.7
NA
+
Health care delivery variable
Overall proportion
Long-term treatment
⫺
a
Regular source of medical care
a
b
b
HIV specialty carea
NOTE.
a
b
NA, not applicable.
Proportions of each group receiving each type of treatment or care are shown in table 1.
P ! .001; x2 test.
no long-term treatment group. Alternatively, some persons in
the long-term treatment groups might have had previous residential care.
A regular source of medical care was defined as a provider
that was visited at least twice by a study patient during 1996 and
that conducted 135% of all outpatient medical encounters with
that patient in that same year [13]. These providers could be
clinics, group practices, or individual physicians but excluded
such health-care providers as radiologists and ED physicians.
When 11 provider could be considered the regular source, we
selected the regular medical provider according to a previously
developed hierarchy of specialists [9]. For HIV-positive persons
only, we identified any visits in 1996 to clinics or private physicians with an agreement with New York State to offer HIVrelated services and expertise in exchange for higher Medicaid
payment rates or from a provider of infectious diseases care [14,
15].
Patient demographic data were obtained from claims and
Medicaid eligibility files and included age, sex, and New York
State area of residence (determined from zip codes). New York
State Medicaid files do not contain reliable data on ethnicity.
Data on the following comorbid conditions were also defined,
on the basis of International Classification of Diseases, version
9, Clinical Modification codes, for inpatient and outpatient
claims files in 1996: mental health disorders (e.g., depression,
non–drug-related psychoses, and anxiety), chronic diseases
other than HIV infection (e.g., diabetes), and clinical AIDS (in
the HIV-positive cohort). We calculated the total hospital days
in 1996 as a proxy for unmeasured health status. Because of
skewed distribution, we log-transformed these data and used
quartiles of the log-transformed hospital days data as a categorical variable in our analysis.
After examining bivariate associations between all covariates
and 2 main end points—repeated ED use and hospitalization—
we estimated multivariable logistic regression for each outcome
in the HIV-positive and the HIV-negative groups. We wanted to
use similar specifications of variables for the 2 groups but had
to compromise between goodness-of-fit, as assessed by the Hosmer-Lemeshow statistic, and comparability of models. The Hosmer-Lemeshow statistics for the reported models for repeated
ED use and hospitalization in the HIV-positive group were in
the acceptable range (0.28 and 0.14, respectively), whereas in the
HIV-negative group, the fit was not as good (0.07 and 0.01,
respectively). Differing specification of some of the variables in
the models did improve the fit. However, the effects of the key
independent variable (i.e., drug treatment category) were consistent across all models in the HIV-positive and HIV-negative
groups regardless of the specification of the other variables in
the models. Therefore, we report models with similar specifications of the variables in both HIV status groups. Analyses were
done with SAS software, version 8.0 (SAS Institute).
RESULTS
Among the 11,556 HIV-positive drug users, 39.5% were in longterm methadone treatment, 1.1% were receiving long-term,
Drug Treatment and Hospital Use among IDUs • CID 2003:37 (Suppl 5) • S459
Table 3. Adjusted associations of health-care delivery, demographic, and clinical characteristics with repeated emergency
department use in 1997 for a cohort of HIV-positive and HIVnegative drug users in New York State.
Adjusted OR (95% CI)
HIV⫺
HIV+
Characteristic
Health care delivery
Long-term treatment
Drug-free
1.00
Methadone
1.25 (0.79–2.09)
1.00
0.95 (0.80–1.13)
None
1.65 (1.04–2.75)
1.37 (1.17–1.62)
No
1.00
1.00
Yes
0.88 (0.81–0.96)
1.22 (1.16–1.28)
Regular source of medical
care
HIV specialty care
No
1.00
Yes
0.99 (0.90–1.08)
NA
Demographic
Sex
Male
1.00
1.00
Female
1.17 (1.07–1.28)
1.02 (0.98–1.07)
Age in years
!30
1.00
1.00
30–39
0.83 (0.71–0.97)
1.00 (0.94–1.07)
40–49
0.66 (0.56–0.77)
0.87 (0.81–0.93)
⭓50
0.60 (0.48–0.75)
0.76 (0.69–0.84)
Area of residence
New York City
1.00
1.00
New York City suburbs
1.21 (0.99–1.48)
1.11 (1.02–1.20)
Upstate urban
1.42 (1.16–1.72)
1.34 (1.26–1.43)
Small city
2.20 (1.46–3.30)
1.98 (1.80–2.19)
Rural
1.80 (1.24–2.59)
1.67 (1.53–1.82)
Clinical
Chronic diseases other
than HIV infection
None
1.00
1.00
1
1.49 (1.33–1.66)
1.77 (1.67–1.88)
2
1.96 (1.62–2.37)
2.08 (1.87–2.31)
⭓3
2.05 (1.41–2.96)
2.81 (2.34–3.39)
Mental health disorder
No
1.00
1.00
Yes
1.07 (0.97–1.19)
1.37 (1.31–1.44)
NOTE. Data also adjusted for log inpatient hospital days in 1996. NA, not
applicable.
medically supervised drug-free treatment, and 59.4% were receiving no longitudinal drug treatment, whereas among the
46,687 HIV-negative drug users, these proportions were 24.3%,
2.5%, and 73.2%, respectively. Even though the proportions of
S460 • CID 2003:37 (Suppl 5) • Turner et al.
persons receiving long-term drug-free treatment are relatively
small, roughly 125 HIV-positive and 1150 HIV-negative persons
received this type of care. Comparison of the HIV-positive and
HIV-negative groups is shown in table 1. In both groups, the
most common drug of abuse diagnosed by health-care providers for persons in drug-free treatment was cocaine (30.2% and
23.5%, respectively) versus only 17.7% and 9.1%, respectively,
for patients receiving methadone. However, usually the type of
drug abuse or dependence was unspecified.
Overall, 25% of the HIV-positive group used the ED repeatedly, compared with 22.1% of the HIV-negative group, and
55% of the HIV-positive group were hospitalized, compared
with 37.5% of the HIV-negative group (table 2). In both groups,
the drug treatment category was significantly associated with
repeated use of the ED and hospitalization. Overall, persons
not receiving long-term drug treatment were most likely to use
these services. In the HIV-positive group, those receiving longterm methadone and drug-free treatment had similar rates of
repeated ED use, whereas those receiving methadone were more
likely to be hospitalized than persons in the drug-free treatment
group. In the HIV-negative group, more-minor differences appeared. Other types of care generally showed less strong differences for both outcomes in both groups.
Compared with persons receiving long-term, medically supervised drug-free treatment, the adjusted odds of using the
ED repeatedly were significantly increased for persons without
this care but similar for those receiving long-term methadone
treatment (table 3). These findings held true for both HIVpositive and HIV-negative groups, but the benefit of treatment
was weaker in the latter group. The presence of a usual source
of medical care had opposite effects for HIV-positive and HIVnegative drug users, with lower adjusted odds for the former
group and higher odds for the latter group. HIV specialty care
showed no effect on repeated ED use. HIV-positive women
were more likely to use the ED, but there was no effect with
respect to sex in the HIV-negative group. Increasing age was
negatively associated with ED use in both groups. In both
groups, persons who lived outside of New York City were more
likely to use the ED repeatedly. The adjusted odds of repeated
ED visits rose with the number of non–HIV-specific chronic
conditions. Mental health disorders were associated with ED
use only in the HIV-negative group.
Persons receiving methadone treatment and those not receiving long-term drug treatment had significantly increased
adjusted odds of hospitalization, compared with drug users
receiving long-term, medically supervised drug-free treatment
(table 4). This effect was strongest in the HIV-positive group.
The adjusted odds of hospitalization for persons with a usual
source of care was significantly lower for the HIV-positive group
only, and HIV specialty care showed an independent protective
Table 4. Adjusted associations of health-care delivery, demographic, and clinical characteristics with hospitalization in 1997
for a cohort of HIV-positive and HIV-negative drug users in New
York State.
Adjusted OR (95% CI)
HIV⫺
HIV+
Characteristic
Health care delivery
Long-term treatment
Drug-free
1.00
Methadone
1.69 (1.14–2.55)
1.00
1.16 (1.00–1.35)
None
1.91 (1.29–2.88)
1.58 (1.36–1.83)
No
1.00
1.00
Yes
0.84 (0.78–0.91)
0.99 (0.95–1.03)
Regular source of medical
care
HIV specialty care
No
1.00
Yes
0.82 (0.76–0.90)
NA
Demographic
Sex
Male
1.00
1.00
Female
1.08 (0.99–1.17)
0.84 (0.81–0.88)
Age in years
!30
1.00
1.00
30–39
1.06 (0.91–1.24)
1.18 (1.12–1.25)
40–49
1.06 (0.90–1.24)
1.24 (1.16–1.32)
⭓50
0.95 (0.77–1.17)
1.22 (1.12–1.34)
Area of residence
New York City
1.00
1.00
New York City suburbs
1.00 (0.83–1.21)
1.01 (0.94–1.09)
Upstate urban
0.91 (0.75–1.11)
1.06 (1.00–1.12)
Small city
0.72 (0.47–1.10)
0.94 (0.86–1.04)
Rural
1.15 (0.79–1.69)
0.96 (0.88–1.05)
Clinical
Chronic diseases other
than HIV infection
None
1.00
1.00
1
1.23 (1.10–1.37)
1.31 (1.24–1.38)
2
1.50 (1.22–1.85)
1.50 (1.35–1.66)
⭓3
1.79 (1.16–2.87)
2.13 (1.75–2.60)
Mental health disorder
No
1.00
1.00
Yes
1.07 (0.97–1.19)
1.33 (1.27–1.39)
NOTE. Data also adjusted for the log of inpatient days in 1996. NA, not
applicable.
association of the same magnitude. The other effects observed
in the model predicting hospitalization are of similar magnitude
to those observed in the ED model.
DISCUSSION
Repeated ED use and hospitalization indicate poor clinical
health status and, potentially, poor access to care. Many drug
users receive medical care only when crises arise that require
ED or inpatient care [16–20]. In our population-based cohort,
we found significant reductions in the adjusted odds of both
repeated ED use and inpatient care for both HIV-positive and
HIV-negative persons receiving long-term drug treatment.
These results expand our prior analyses that found a favorable
association between reduced hospitalization and outpatient
drug treatment and a usual source of medical care [6]. We
found that drug users not receiving long-term drug treatment
had consistently higher adjusted odds of ED and hospital care
than did drug users receiving medically supervised drug-free
treatment. Drug users receiving long-term methadone treatment had similar ED use but significantly higher adjusted odds
of hospitalization than did persons in drug-free treatment.
Cocaine was the most common type of drug abuse specified
for persons receiving drug-free treatment. Use of cocaine use,
particularly crack cocaine, is common in New York City [21]
and accounts for a large number of ED visits in the United
States [22]. Cocaine abuse is increasingly common in Canada
[23]; in South America, it is most the common drug of abuse,
and its use continues to rise [24, 25]. Injection of cocaine is a
risk factor for HIV infection in South America [26], and cocaine
abuse increases risky sexual practices [27]. Given the detrimental effects of cocaine on personal health and associated
crime in the Americas [28–30], the identification of successful
treatment strategies is a critical public health issue.
In a US study of 1605 cocaine-dependent patients in residential and outpatient medically supervised drug-free treatment
programs, relapse to weekly or more frequent use of cocaine
was lowest for patients treated for ⭓90 days [31]. Others report
that day treatment is a clinically and economically effective
alternative to residential treatment for many cocaine abusers
[32, 33]. For cocaine-dependent patients in both long-term
residential and outpatient drug-free treatment programs, it has
been demonstrated that there are reductions in crime-related
costs, compared with costs before entry into a treatment program [34]. In addition to cost savings, excessive demand for
ED services by drug users may be addressed by accessible drug
treatment [35]. We found that persons not receiving long-term
drug treatment were 130%–60% more likely, depending on
HIV status, to use the ED repeatedly.
Our study focused only on ambulatory treatment for drug
users. This form of care may be useful only for patients with
less severe dependence. Although we studied drug treatment
that lasted for ⭓6 months, other investigators have reported
improved outcomes after only 3 months of treatment [31]. The
optimal duration of medically supervised drug-free therapy is
Drug Treatment and Hospital Use among IDUs • CID 2003:37 (Suppl 5) • S461
not known, but current thinking on drug abuse treatment is
leaning toward longer-term therapy [1].
HIV-positive drug users showed the most marked benefits
of long-term drug treatment on our 2 outcomes. HIV-positive
drug users rely heavily on inpatient care because of drug abuse–
related complications, HIV-related complications, and other
non–HIV-specific diseases. Others have argued that treatment
programs are an integral part of any strategy to decrease hospital use among HIV-positive injection drug users [36]. In the
HIV-positive group, having an HIV specialty provider was associated with a reduced rate of hospitalization. Perhaps this
effect may reflect an improved clinical status of HIV-positive
patients who receive care from persons with more HIV expertise, as has been reported by our group previously [37].
Limitations of our study include the fact that we did not
have primary data on the types of drugs used by study patients.
Second, long-term, medically supervised drug-free treatment
was a relatively uncommon form of drug treatment in this
cohort. Third, we did not study reasons for emergency department and hospital episodes. Hospitalization for detoxification may represent a positive health outcome. Finally, our
data allow us only to speculate on the mechanisms by which
long-term drug treatment decreases ED and hospital care.
Given the paucity of data about addiction programs other
than methadone maintenance programs, these data provide important evidence that medically supervised drug-free treatment
is an effective option for the treatment of addiction to nonopiate drugs. Future studies should examine the mechanisms by
which drug-free treatment achieves its benefits, the types of
drug users who are better candidates for drug-free programs,
the optimal duration of therapy, and the benefits of drug-free
treatment on a wider range of health care outcomes.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
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