Association between metabolic syndrome and cataract: a meta-analysis

Metabolic syndrome (MetS) has been suggested to be associated with an increased risk of cataract in adults. However, the evidence remains inconclusive. This meta-analysis aimed to clarify this potential association.

We conducted a systematic search of PubMed, Embase, and Web of Science up to July 31, 2024, for observational studies evaluating the association between MetS and cataract. Data were pooled using a random-effects model to calculate risk ratios (RR) with 95% confidence intervals (CI). Heterogeneity was assessed with the Cochrane Q test and I² statistics. Subgroup analyses were performed based on study characteristics.

Ten studies with 379,464 participants were included. The meta-analysis showed that MetS was significantly associated with an increased risk of cataract (RR: 1.28, 95% CI: 1.16-1.41, p < 0.001; I² = 90%). Subgroup analyses indicated that the association was stronger in participants aged ≥57 years compared to those <57 years (p for subgroup difference <0.001) and in studies using the International Diabetes Federation criteria for MetS diagnosis compared to the National Cholesterol Education Program criteria (p for subgroup difference <0.001). No significant differences were found by geographic region, sex, or cataract types. Sensitivity analyses confirmed the robustness of these findings. Egger's regression test showed no significant publication bias (p = 0.44).

MetS is associated with an increased risk of cataract in adults, particularly in older populations. Further studies are needed to explore the underlying mechanisms and develop prevention strategies.