1 dose-response relationship between incarceration and non- adherence to haart among injection drug...
TRANSCRIPT
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Dose-response relationship between incarceration and non-adherence to HAART among injection drug users in a Canadian setting
M-J Milloy1,2, T Kerr1,3, J Montaner1,3, E Wood1,3
1. BC Centre for Excellence in HIV/AIDS, St. Paul’s Hospital, Vancouver, BC, Canada;2. School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada;3. Department of Medicine, University of British Columbia, Vancouver, BC, Canada
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INTRODUCTION
• Incarceration: Opportunity to engage individuals in HIV care?– 10% of all HIV+ individuals in US
incarcerated ≥ 1 time/year1
– Clinical trials demonstrated effectiveness of DOT interventions in prisons2,3
1. Spaulding et al., 2009. PLoS ONE.2. Altice et al., 2001. JAIDS.3. Babudieri et al., 2000. JAMA.
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INTRODUCTION
• Effect of incarceration on adherence among IDU remains equivocal– Incarcerated associated with greater risk of
non-suppression1 and discontinuation2
– Effect of long-term patterns of incarceration, release and re-incarceration on HIV treatment remains undetermined
1. Palepu et al., 2003. J Urban Health.2. Kerr et al., 2005. AIDS Care.
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OBJECTIVE
To estimate the effect of the cumulative burden of incarceration on non-adherence to ART among a long-running cohort of community-recruited HIV-seropositive individuals who use injection drugs
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METHODS: Sample
• AIDS Care Cohort to evaluate Exposure to Survival Services (ACCESS):– Ongoing prospective cohort recruited using
community outreach in Vancouver’s Downtown Eastside (DTES)
– Eligibility: HIV+, ≥18 year old, injection drug use in previous month, informed consent
– Current study restricted to ART-exposed
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METHODS: Data
• Every six months, participants respond to interviewer-administered questionnaire– Behavioural data including drug use,
incarceration, housing, etc.• Linkage to Drug Treatment Programme
– Comprehensive ART dispensation records– HIV clinical monitoring (CD4, HIV RNA load)
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METHODS: Measures
• Outcome of interest: Non-adherence to prescribed ART– Non-adherence: < 95% days dispensed of
all days eligible in previous six months– Validated measure based on prescription
refill– Adherence not confounded by financial
ability given universal free access in BC
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METHODS: Measures
• Primary explanatory: Burden of incarceration– Incarceration event: Overnight or longer in youth
detention, local jail, regional prison or federal penitentiary
– Measured longitudinally at each follow-up– Cumulative sum converted into factor:
• Zero events (Reference);• 1 – 2 incarceration events;• 3 – 5 incarceration events;• > 5 incarceration events
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METHODS: Analysis
• Multivariate modeling:– Generalised linear mixed effects – Including primary explanatory variable
(incarceration) and possible confounders: Illicit drug use, housing, socio-demographics, CD4, HIV RNA pVL
– Model built using Greenland et. al’s a priori stepwise backwards procedure
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RESULTS: Sample
• May 1996 to Sept 2009: 490 ART-exposed individuals recruited– 201 (41%) women and 192 (39%)
Aboriginal ancestry– 2220 person-years of follow-up– Median follow-up: 29 months (Inter-quartile
range [IQR]: 0 – 64)
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RESULTS: Incarceration
• Incarceration during study period– 1156 incarceration events among
271(55%) participants– Crude incarceration rate: 53 per 100
person-years (95% Confidence Interval [CI]: 50 – 56 per 100)
– Median # incarceration events among incarcerated: 3 (IQR: 1 – 6)
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DISCUSSION
• Cumulative burden of incarceration a strong predictor of non-adherence– Dose-dependent relationship between
incarceration and non-adherence– Increasing number of incarceration cycles
present elevating barrier to adherence– Finding considers effect of incarceration
within course of HIV disease among IDU
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DISCUSSION
• Prison-related barriers to adherence1
– Short-term interruptions common in intake and post-release periods
– Disruptions caused by transitions between correctional/non-correctional settings
– Lack of capacity for HIV care among prison medical staff
– HIV-related stigma among prisoners
1. Small et al., 2009. AIDS Care.
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DISCUSSION
• HIV treatment efforts among IDU should directly address incarceration1
– Reform prison health care to improve access and adherence to ART
– Reduce exposure to incarceration through community diversion
1. Maru et al., 2007. Lancet ID.
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DISCUSSION
• Time to consider a risk environment for HIV disease progression?– Risk environment framework1: HIV
transmission risk produced by individual, social, enviromental and structural factors
– Increasing evidence of importance of social, structural and environmental context in producing adherence among IDU
1. Rhodes et al., 2005. Soc Sci Med.
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DISCUSSION
• Study limitations:– ACCESS not a random sample of HIV-
positive IDU; results may not be generalizable to other settings and other correctional systems
– Incarceration not randomly assigned; observed association may be under influence of unmeasured confounding
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CONCLUSION
– Dose-dependent relationship between cumulative burden of incarceration and non-adherence to ART
– Finding illuminates structural-level barrier to adherence among IDU
– Efforts to deliver HIV treatment to IDU must consider role of incarceration
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ACKNOWLEDGEMENTS
• ACCESS participants• Deborah Graham, Tricia Collingham, Caitlin Johnston, Steve
Kain, Calvin Lai for their research and administrative assistance• The ACCESS study is supported by United States National
Institutes of Health (R01DA021525) and Canadian Institutes of Health Research (MOP-79297, RAA-79918)
• Dr. Kerr is supported by the Michael Smith Foundation for Health Research and the Canadian Institutes of Health Research
• Mr. Milloy is supported by the Canadian Institutes of Health Research