LAUSR

OBJECTIVE Isoniazid (INH) preventive therapy is recommended to prevent tuberculosis (TB) disease for persons with HIV (PWH), except for those with regular and heavy alcohol consumption, due to hepatotoxicity concerns. We aimed to quantify the incidence of severe INH-related toxicity among PWH with and without recent alcohol consumption. DESIGN Prospective study of PWH receiving INH. METHODS We included PWH in southwest Uganda with recent (prior three months) (n = 200) or no (prior year) self-reported alcohol consumption (n = 101), on antiretroviral therapy, TB infected (≥5 mm on tuberculin skin test), and alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2x the upper limit of normal (ULN). Grade 3+ INH-related toxicity was ALT or AST ≥5x the ULN or severe symptoms; we stopped IPT upon detection. Grade 2 INH-related toxicity was ALT or AST 2-5x the ULN or moderate symptoms. RESULTS The cumulative incidence of Grade 3+ INH-related toxicity was 8.3% (95% CI: 5.7-12.0); all resolved after INH cessation. Incidence was 6.0% (95% CI: 3.1-10.2) among those reporting recent alcohol use and 12.9% (95% CI: 7.0-21.0) of those reporting no prior year alcohol use. We found no differences by baseline phosphatidylethanol-confirmed alcohol severity. The cumulative incidence of Grade 2 toxicities (without Grade 3+) was 21.7% (95% CI: 17.2-27.0); 25.0% (95% CI: 19.0-31.8) among those with recent alcohol use and 14.8% (95% CI: 8.1-23.9) among those with no prior year alcohol use. CONCLUSIONS Alcohol use does not appear to increase risk for serious INH-related toxicity among PWH without significant liver enzyme elevations at baseline (≤2x ULN).