Circumcision for HIV Prevention in Men Who Have Sex With Men: An Updated Meta-Analysis

Area of Science:

• Public Health
• Epidemiology
• Infectious Disease Prevention

Background:

• Male circumcision is known to reduce HIV risk in heterosexual men, but its effect on men who have sex with men (MSM) has been unclear due to inconsistent data.
• Previous studies on MSM were confounded by regional differences and lacked robust evidence, despite a recent trial suggesting protection in primarily-insertive MSM (PI-MSM).

Purpose of the Study:

• To clarify the association between male circumcision and HIV risk specifically among PI-MSM.
• To conduct a rigorous meta-analysis, adjusting for confounding factors, to determine the protective effect of circumcision in this population.

Main Methods:

• An updated literature search identified 49 studies for descriptive analysis.
• Random-effects meta-analyses were performed, first unadjusted and then adjusted for confounders, comparing HIV risk in PI-MSM versus other MSM.
• Publication bias and regional heterogeneity were assessed to ensure the validity of the findings.

Main Results:

• The unadjusted meta-analysis showed a reduced HIV risk with circumcision in PI-MSM (OR=0.57), though with bias and heterogeneity.
• The confounder-adjusted meta-analysis revealed a significant protective effect of circumcision for PI-MSM (OR ratio=0.53), with no significant publication bias or regional heterogeneity.
• Ten studies contributed to the confounder-adjusted meta-analysis, providing robust evidence.

Conclusions:

• Male circumcision demonstrates a substantial protective effect against HIV infection among PI-MSM.
• These findings strongly support the implementation of male circumcision as an effective HIV prevention strategy for PI-MSM.