Degree of Myopia and Glaucoma Risk: A Dose-Response Meta-analysis

Purpose: To verify the dose-response relation between the degree of myopia and open-angle glaucoma (OAG) risk DESIGN: Dose-response meta-analysis.

Methods: We searched the PubMed, EMBASE, and Cochrane Library databases for population-based studies published until November 30, 2020, and reporting on both myopia and OAG. Random-effect models generated pooled odds ratios (OR) and 95% CIs. Results robustness was confirmed by influence and subgroup analyses. A 2-stage dose-response meta-analysis calculated the OAG risk per unit dose of myopia (spherical equivalent [SE] decrease of 1 diopter [D]) and examined the relationship pattern.

Results: The meta-analysis comprised 24 studies in 11 countries (514,265 individuals). The pooled OR of any myopia degree's association with OAG was 1.88 (95% CI, 1.66-2.13; I² = 53%). The OR differences based on ethnicity (Asians vs Westerners) or 5 geographic areas were not statistically significant (P = .80 and P = .06, respectively). The pooled ORs of the associations between low, moderate, moderate-to-high, high myopia, and OAG were 1.50 (95% CI, 1.29-1.76), 1.69 (95% CI, 1.33-2.15), 2.27 (95% CI, 1.74-2.96), and 4.14 (95% CI, 2.57-6.69), respectively. According to the dose-response meta-analysis, the pooled OR (per SE 1-D change) was 1.21 (95% CI, 1.15-1.28). The OAG risk accelerated at approximately -6 D, and further accelerated from -8 D, showing a nonlinear concave upward slope (P = .03).

Conclusions: For each unit (1-D) increase in myopia, the risk of glaucoma increases by approximately 20%. The risk more steeply increases in high-degree myopia, representing a significant nonlinear relationship.