The last few decades have seen a pandemic of human immunodeficiency virus (HIV)/
acquired immunodeficiency syndrome (
AIDS), which continues to cause substantial morbidity and mortality. ABO
blood groups are anthropological and genetic characteristics of a population whose associations with
HIV infection are still controversial. This systematic review with meta-analysis was undertaken to investigate whether certain
blood groups may have associations with
HIV infection. PubMed, Scopus and Web of Science databases were systematically searched as of 6 September 2021. Grey literature was identified through screening Google Scholar, and reference lists of relevant studies. All observational studies providing data on
ABO blood group distribution among HIV-infected and uninfected participants were included. Using a random effect model, risk ratios (RR) and 95% confidence intervals (CIs) were pooled to quantify this relationship. Fifty eligible studies with a total of 3,068,244 participants and 6508 HIV-infected cases were included. The overall analysis found that
blood group AB increased the risk of
HIV infection by 19% as compared with non-AB
blood groups (RR = 1.19, 95% CI: 1.03-1.39, p = 0.02). Pooled estimates for other
blood groups failed to reach statistical significance. Subgroup analyses identified a positive relationship between AB
blood group and
HIV infection within Asia, patient populations (as opposed to blood donors and general populations), studies with lower sample sizes, high-income countries and studies with a moderate quality score. The sequential omission and re-analysis of studies within sensitivity analyses produced no change in the overall pooled effect. In conclusion, this study identified that
blood group AB carriers were more susceptible to
HIV infection. Future investigations should be directed toward clarification of the exact role of ABO
blood groups in
HIV infection and the possible underlying mechanisms.