Strathdee SA, Palepu A, Cornelisse PGA, Yip B, O'Shaughnessy MV, Montaner JSG, Schechter MT, Hogg RS. Barriers to Use of Free Antiretroviral Therapy in Injection Drug Users. JAMA. 1998;280(6):547-549. doi:10.1001/jama.280.6.547
From the British Columbia Centre for Excellence in HIV/AIDS, St Paul's Hospital (Drs Strathdee, Palepu, O'Shaughnessy, Montaner, Schechter, and Hogg, Mr Cornelisse, and Ms Yip), Departments of Health Care and Epidemiology (Drs Strathdee, Schechter, and Hogg) and Medicine (Drs Palepu and Montaner), Faculty of Medicine, University of British Columbia, Vancouver, British Columbia (Dr Strathdee is now at the Johns Hopkins University School of Hygiene and Public Health, Baltimore, Md).
Context.— In British Columbia, human immunodeficiency virus (HIV)–infected
persons eligible for antiretroviral therapy may receive it free but the extent
to which HIV-infected injection drug users access it is unknown.
Objective.— To identify patient and physician characteristics associated with antiretroviral
therapy utilization in HIV-infected injection drug users.
Design.— Prospective cohort study with record linkage between survey data and
data from a provincial HIV/AIDS (acquired immunodeficiency syndrome) drug
Setting.— British Columbia, where antiretroviral therapies are offered free to
all persons with HIV infection with CD4 cell counts less than 0.50×109/L (500/µL) and/or HIV-1 RNA levels higher than 5000 copies/mL.
Subjects.— A total of 177 HIV-infected injection drug users eligible for antiretroviral
therapy, recruited through the prospective cohort study since May 1996.
Main Outcome Measures.— Patient use of antiretroviral drugs through the provincial drug treatment
program and physician experience treating HIV infection.
Results.— After a median of 11 months after first eligibility, only 71 (40%) of
177 patients had received any antiretroviral drugs, primarily double combinations
(47/71 [66%]). Both patient and physician characteristics were associated
with use of antiretroviral drugs. After adjusting for CD4 cell count and HIV-1
RNA level at eligibility, odds of not receiving antiretrovirals were increased
more than 2-fold for females (odds ratio [OR], 2.53; 95% confidence interval
[CI], 1.08-5.93) and 3-fold for those not currently enrolled in drug or alcohol
treatment programs (OR, 3.49; 95% CI, 1.45-8.40). Younger drug users were
less likely to receive therapy (OR, 0.47/10-y increase; 95% CI, 0.28-0.80).
Those with physicians having the least experience treating persons with HIV
infection were more than 5 times less likely to receive therapy (OR, 5.55;
95% CI, 2.49-12.37).
Conclusions.— Despite free antiretroviral therapy, many HIV-infected injection drug
users are not receiving it. Public health efforts should target younger and
female drug users, and physicians with less experience treating HIV infection.
THE NUMBER of human immunodeficiency virus (HIV)–infected injection
drug users (IDUs) recently increased in Vancouver, British Columbia.1,2 Prevalence and incidence of HIV were
reported as 25% and 18.6 per 100 person-years, respectively.2
Advances in antiretroviral therapy (ART) have improved survival in British
Columbia3 and elsewhere.4,5
Also, treated subjects experiencing decreases in HIV-1 RNA below detectable
levels may be less infectious.6,7
Despite this, physicians may be less likely to recommend ART for IDUs because
of the belief that IDUs are less adherent to complex regimens, which could
promote selection of drug-resistant strains.8
In British Columbia, all HIV-positive persons eligible for ART according to
guidelines9,10 have free access
to it through a province-wide HIV/AIDS (acquired immunodeficiency syndrome)
drug treatment program. To estimate the proportion of eligible IDUs receiving
ART, we linked survey data with data from the drug treatment program. We also
attempted to identify barriers to ART utilization.
Beginning in May 1996, 1106 IDUs were recruited into a prospective cohort
study through self-referral and street outreach.2
Subjects were eligible if they had injected illicit drugs at least once in
the previous month, resided in the greater Vancouver region, and provided
written informed consent. Most subjects (82%) were volunteers who had learned
of the study via other participants or recruitment materials. Others were
referred by storefront agencies (15%) or clinics (3%). At baseline and semiannually,
subjects provided blood samples and completed an interviewer-administered
questionnaire. Baseline survey data pertained to the previous 6 months and
included sociodemographics, physician visits, drug use, and attendance at
needle exchanges and drug or alcohol treatment programs. At each visit, CD4
cell counts and plasma HIV-1 RNA levels (Amplicor; Roche Molecular Systems,
Branchburg, NJ) were assessed.
Subjects were included if testing HIV positive at cohort entry, aware
of HIV status, eligible for ART,9,10
or receiving ART through the program by August 31, 1997. To assess the proportion
of eligible subjects receiving ART, nonnominal cohort data were linked to
program data. The study was approved by the University of British Columbia
and St Paul's Hospital.
Free ART has been available since 1986.3
Since 1992, when double combinations were available for those with CD4 cell
count of 0.35 × 109/L (350/µL) or less, ART has been
distributed to more than 4000 persons meeting guidelines criteria.9,10 Pharmaceutical sales suggest that
less than 1% of HIV-infected British Columbians purchase ART outside the program
(Pharmacare, British Columbia Ministry of Health, unpublished data, 1998).
Combination therapy access was expanded to those with CD4 cell count of less
than 0.50×109/L in December 1995. In July 1996, triple combinations
were available to ART-naive persons with CD4 cell count of less than 0.50
× 109/L and/or HIV-1 RNA level higher than 100000 copies/mL,
and double combinations to those with CD4 cell count of less than 0.50×109/L and/or HIV-1 RNA level of 5000 to 100000 copies/mL. Physicians enrolling
a patient (a Canadian citizen or landed immigrant [may legally reside and
work in Canada]) in the program complete a drug request form with which patient
baseline and physician data are collected.
Treated and untreated subjects were compared regarding self-reported
demographic and behavioral information, using contingency table analysis.
Program enrollment data were used to assign a level of physician HIV-related
experience for each subject, estimated via cumulative number of patients receiving
ART within their practice, by the date of subject's first known eligibility.
To assess independent predictors of never receiving ART, variables significant
in univariate analyses (P<.05) were considered
for inclusion in a multivariate logistic regression model, adjusting for CD4
cell count and HIV-1 RNA level at eligibility. This model assumed a linear
relationship between independent variables and log odds of never receiving
ART. The few subjects with missing values were excluded from multivariate
models. Corresponding odds ratios (ORs) and test-based 95% confidence intervals
(CIs) were computed. All 2-way interactions were evaluated.
Of 191 seropositive IDUs aware of their serostatus, 177 met ART eligibility
guidelines. Of these, 71 (40%) had received any ART. Median time since eligibility
was 11 months for treated and untreated subjects (P=.10).
At entry into the program, 12 (17%) received monotherapy, 47 (66%) double
combinations, and 12 (17%) triple therapy. Most (80%) received therapy meeting
guidelines at enrollment. We defined adherence as ratio of number of months
patients received ART refills relative to total number of months they should
have received ART, by which definition 37% were 80% adherent.
Characteristics associated with not receiving therapy are included in Table 1. The CD4 cell count and HIV-1 RNA
level did not differ at eligibility for untreated and subsequently treated
subjects. Groups did not differ by self-reported drug use, housing, or needle
exchange program attendance. Compared with other IDUs receiving ART, no significant
differences emerged regarding gender, age, CD4 cell count, or HIV-1 RNA level
After simultaneously adjusting for CD4 cell count and HIV-1 RNA level
at eligibility, patient and physician characteristics were associated with
ART use (Table 2). A multivariate
logistic regression model showed more than 2-fold increased odds of not receiving
ART for females, and 3-fold increased odds for IDUs not currently enrolled
in drug or alcohol treatment programs. Younger IDUs were less likely to receive
ART. Those with physicians having the lowest level of HIV experience were
more than 5 times less likely to receive ART. Results were unchanged after
adjusting for time since eligibility and other factors. No significant interactions
Despite free ART in British Columbia, less than half the IDUs in our
sample received therapy about 1 year after becoming eligible. After accounting
for CD4 cell count and HIV-1 RNA level, barriers to ART use included both
physician and patient characteristics, suggesting that a multifaceted approach
is needed to maximize ART use.
Physicians with the least ART experience were more than 5 times less
likely to prescribe ART for IDUs, relative to most experienced physicians.
Physician HIV/AIDS experience was substantially associated with patient survival
in prior reports.11,12 Previously,
we showed that physician experience was associated with practice concordance
with therapeutic HIV/AIDS guidelines.13 Also,
motivated IDUs may select physicians with a higher HIV/AIDS caseload.
One could argue that the low overall ART uptake seen reflected exclusion
of less adherent patients by physicians, possibly related to the association
between enrollment in drug or alcohol treatment programs and ART use. However,
we found no markers of social instability such as income assistance, unstable
housing, or incarceration associated with ART use.
Injection drug users not enrolled in drug or alcohol treatment programs
were 3 times less likely to receive ART. These IDUs may be less concerned
about their health, and less willing to initiate ART. Also, rehabilitation
programs may facilitate access to clinicians who are more likely to prescribe
ART. Similar findings were reported regarding IDUs offered zidovudine and
opportunistic infection prophylaxis in Connecticut.14
Drug abstinence was also associated with receiving ART in a study in Baltimore,
Young IDUs were less likely to receive ART. They may be less aware of
ART benefits, and less likely to seek care. Alternatively, clinicians may
be less likely to prescribe ART for them if they perceive that young IDUs
are less able to adhere to complex regimens.
Female IDUs were twice less likely to receive ART than males after adjusting
for baseline characteristics. In prior reports, females were less likely than
males to receive zidovudine after accounting for clinical and sociodemographic
variables.16,17 Although some
US studies did not find sex to significantly predict health service use in
HIV infection,15,18 a study of
persons with AIDS found that females were less likely to use health care services
such as hospitalization than were males.19
In our cohort, females with HIV infection reported higher use of hospital
and emergency department services than did males with infection,20
suggesting that differential access to care cannot explain sex differences
in ART use.
A limitation of our analysis is the inability to explore reasons for
patient- and physician-specific barriers to ART use. It is possible that in
the clinical judgment of the physician, prescribing ART would have been inappropriate
in certain situations. Also, physicians may have prescribed treatment that
was not taken. In subsequent analyses of 120 of the 177 subjects, 94 (78.3%)
were given a prescription for ART and 48 (51.1%) had it filled. Although not
necessarily generalizable, these figures support the findings reported herein.
Since subjects were largely volunteers and tended to belong to the lowest
socioeconomic strata, caution should be exercised in generalizing results.
However, demographic characteristics of subjects did not differ from those
of other IDUs in the drug treatment program. We may have overestimated the
proportion of IDUs receiving ART, as some subjects may have been referred
for therapy because of study participation. As this is a cross-sectional analysis,
we cannot infer causal relationships. Although recall bias may have influenced
self-reports, data pertaining to physician HIV experience and ART use were
obtained independently from the drug treatment program.
Studies in the United States indicate that ART access may be limited
by lack of third-party reimbursement.15,16,21
We found that barriers to ART use persist in IDUs with HIV infection, despite
universal health care and free ART. Less experienced physicians and subgroups
such as female and young IDUs may require targeted interventions to increase
access to effective HIV treatment to enhance survival and possibly decrease
risk of HIV transmission.