Background Few prospective studies have examined the association between alcohol use and sexually transmitted infections (STI) among African women. We evaluated whether alcohol use was associated with increased risk of STI in a cohort of Kenyan women.
Methods We analysed data from a prospective study of women who report transactional sex in Mombasa. Women 18 and older who enrolled between 2006 and 2011 were included. Participants could contribute up to two years of follow-up. Baseline alcohol use was categorised as none, 1–7, or ≥ 8 drinks/week. STIs (gonorrhoea, Chlamydia, and Trichomonas) and sexual risk behaviours were assessed monthly. The association between alcohol use and any STI was evaluated by logistic regression using generalised estimating equations.
Results Overall, 622 women contributed 368 person-years of observation. Of these, 161(25.8%) were HIV-positive. Among HIV-positive women, 88 (54.7%) reported 1–7 drinks/week and 31 (19.3%) reported ≥ 8 drinks/week. Among HIV-negative women, 248 (53.8%) reported 1–7 drinks/week and 100 (21.7%) reported ≥ 8 drinks/week. The association between alcohol use and STI risk was significantly different in HIV-positive compared to HIV-negative women (p = 0.05). Alcohol use was associated with STI acquisition only in HIV-positive women. Compared to non-drinkers, women who drank 1–7 drinks (odds ratio [OR] = 2.3 [1.0–5.5]) and ≥ 8 drinks/week (OR = 3.2 [1.0–10.6]) had increased risk of STI. These associations were similar though no longer statistically significant after adjusting for age, workplace and marijuana use (1–7 drinks OR = 2.3 [1.0, 5.3]; ≥ 8 drinks OR = 2.0 [0.7, 6.1]).
Conclusion In this prospective analysis, baseline alcohol use was associated with an increased risk of STI among HIV-positive women. Addressing alcohol use problems in HIV care settings may offer additional benefits of reducing the burden of STIs among high-risk African women. Future research with time-varying measures of alcohol use will be important to further characterising the relationships between alcohol and STI risk in this population.