Isoniazid preventive therapy (IPT) is a key strategy to decrease tuberculosis (TB) disease development in people living with HIV (PLHIV). Unhealthy alcohol use is associated with increased risk of progression to TB disease and reduced adherence to antiretroviral therapy (ART), but its effect on IPT adherence is not well known. We sought to determine the level of adherence to IPT, overall and by drinking status among PLHIV in Uganda.
This was a prospective study of PLHIV with confirmed latent TB infection (LTBI), all on ART, in a large HIV clinic in Southwestern Uganda. We recruited 200 PLHIV reporting any current (prior 3 months) alcohol use and 102 PLHIV reporting no alcohol consumption for at least 1 year. All received IPT. We monitored adherence with Medication Event Monitoring System (MEMS) caps. Our primary outcome, sub-optimal INH adherence, was defined as <90% of days with any MEMS opening in the prior 90 days. Alcohol use was captured by a composite measure of the Alcohol Use Disorders Identification Test – Consumption (AUDIT-C) and phosphatidylethanol (PEth), an alcohol biomarker. Alcohol use was categorized as: none: no self-report, and PEth <8 ng/mL; moderate: AUDIT-C 1-2 (women) or 1-3 (men), and/or PEth 8-<50 ng/mL; unhealthy: AUDIT-C ?3 (women) or ?4 (men), and/or PEth ?50 ng/mL. We used generalized estimating equations logistic regression to assess the association between the alcohol use and sub-optimal INH adherence, adjusting for age, gender, ART adherence, study time on INH, symptoms of depression, Grade 2+ liver enzyme elevations or symptoms and social support.
Of the 302 enrolled persons, 279 were on INH for three or more months. Half (50.9%) were female and 21.9% and 50.5% were in the moderate and unhealthy alcohol groups, respectively. Overall prevalence of sub-optimal INH adherence was 31.3% at 3 months and 43.9% at 6 months. The odds of sub-optimal INH adherence were significantly higher for those in the unhealthy (adjusted odds ratio [aOR] 2.52 (95% CI: 1.48-4.30)) alcohol group but not in the moderate (aOR 1.46 (95% CI: 0.87-2.45)) group, compared to no alcohol consumption group.
Sub-optimal adherence to INH at 3- and 6-months was high among PLHIV and was associated with unhealthy alcohol use. Adherence support and/or alcohol reduction strategies are needed for this group at high risk for active TB.