American Research Journal of Biosciences

Background: Despite the proven efficacy of pre-exposure prophylaxis (PrEP) in preventing HIV infection, adherence remains inconsistent, particularly among individuals with alcohol use and intersecting psychosocial or structural challenges. This umbrella review synthesized evidence on how alcohol consumption influences PrEP adherence, discontinuation, and related HIV and sexually transmitted infection (STI) outcomes, with emphasis on population specific and severity-related dimensions. Methods: Following PRISMA and AMSTAR-2 standards for umbrella reviews, a systematic search was conducted across MEDLINE, Embase, Cochrane Library, PsycINFO, Scopus, and Web of Science for peer-reviewed systematic reviews and meta-analyses published between January 2006 and June 2025. Twenty-two reviews met the inclusion criteria. Screening and data extraction were performed in Covidence and REDCap, with overlap quantified by Corrected Covered Area. Quantitative credibility, heterogeneity, and risk-of-bias metrics guided evidence weighting. Results: Across pooled analyses, adherence above 70 % reduced HIV acquisition risk by roughly 75 % (RR ≈ 0.25 – 0.30), while adherence below 60 % yielded negligible protection (RR ≈ 0.95). Hazardous drinking was associated with a 25 – 35 % reduction in adherence and 2-fold higher odds of discontinuation. Baseline STI prevalence among PrEP users averaged 24 %, with incidence near 72 per 100 person-years, indicating overlapping vulnerability. Provider barriers included low PrEP familiarity (≈ 60 %) and limited prescribing confidence (< 35 %). Transgender and gender diverse populations showed PrEP use under 10 %, constrained by stigma, cost, and perceived hormone interactions. Conclusion: Alcohol use and co-occurring psychosocial stressors substantially erode PrEP adherence and continuity, amplifying HIV and STI risks despite pharmacologic efficacy. Integrating alcohol-reduction counseling, mental-health support, and long-acting PrEP delivery within gender-affirming, low-barrier systems is critical to sustain prevention gains and reduce inequities.