For a systematic review and meta-analysis, researchers highlighted the known data linking alcohol consumption to intraocular pressure (IOP) and open-angle glaucoma (OAG). Understanding and measuring these relationships might help therapeutic recommendations or treatment techniques and give information on illness causation. Alcohol’s role in influencing IOP and OAG risk, as a modifiable factor, may potentially be of relevance from an individual or public health standpoint. The protocol for the study was already filed in the Open Science Framework Registries. Eligible publications from three databases (PubMed, Embase, and Scopus) were independently screened and quality graded by two reviewers (May 14, 2021). All case-control, cross-sectional, and cohort studies that reported a quantifiable effect estimate and 95% CI for the relationship between alcohol consumption and IOP or OAG were included. The data for IOP and OAG correlations were qualitatively summarized. Random-effects meta-analysis was used to pool effect estimates for the OAG relationship. Studies that did not match the strict inclusion criteria for the systematic review but had relevant results were also evaluated and discussed. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was used to assess the certainty of evidence.

The systematic review included thirty-four studies. Although absolute effect sizes were small, eleven studies demonstrating a link with IOP show that frequent alcohol consumption is related to greater IOP and the prevalence of ocular hypertension (IOP>21 mmHg). Eleven of the 26 studies evaluated for a connection with OAG and included 173,058 people fulfilled the inclusion criteria for meta-analysis. Pooled effect estimates revealed a positive relationship between any alcohol consumption and OAG (1.18; 95% CI, 1.02–1.36; P = 0.03; I^2 = 40.5%), with comparable values for both prevalent and incident OAG. The overall GRADE level of evidentiary certainty was extremely poor.

Although the meta-analysis reveals a negative relationship between alcohol usage and OAG, the findings should be regarded with caution due to the underlying evidence base’s inadequacy and heterogeneity, the modest absolute impact size, and the questionable statistical significance. Nonetheless, the findings may be therapeutically useful, and future research should concentrate on enhancing evidence quality.