Improving estimation of the association between alcohol use and intimate partner violence in low-income and middle-income countries

Background Alcohol use is a consistent correlate of intimate partner violence (IPV) in low-income and middle-income countries (LMICs). However, the magnitude of this association differs across studies, which may be due to contextual and methodological factors. This study aims to estimate and explore sources of heterogeneity in the association between alcohol use and IPV in 28 LMICs (n=109 700 couples). Methods In nationally representative surveys, partnered women reported on IPV victimisation and male partner's alcohol use. We estimated the relationship between alcohol use and IPV using logistic regression and full propensity score matching to account for confounding. Country-specific ORs were combined using a random-effects model. Country-level indicators of health and development were regressed on ORs to examine sources of variability in these estimates. Results Partner alcohol use was associated with a 2.55-fold increase in the odds of past-year IPV victimisation (95% CI 2.27 to 2.86) with substantial variability between regions (I 2 =70.0%). Countries with a low (<50%) prevalence of past-year alcohol use among men displayed larger associations between alcohol use and IPV. Exploratory analyses revealed that colonisation history, religion, female literacy levels and substance use treatment availability may explain some of the remaining heterogeneity observed in the strength of the association between alcohol use and IPV across countries. Conclusion Partner alcohol use is associated with increased odds of IPV victimisation in LMICs, but to varying degrees across countries. Prevalences of male alcohol use and cultural factors were related to heterogeneity in these estimates between countries.