Relationship between vitamin D deficiency and diabetic retinopathy: a meta-analysis

The purpose of this study was to evaluate the evidence for an association between diabetic retinopathy (DR) and vitamin D deficiency.

Meta-analysis.

We included 14 observational studies with 10 007 participants who had undergone assessment for both DR and vitamin D deficiency. Pooled odds ratios (ORs) and 95% CIs were calculated using a random-effect, Mantel-Haenszel analysis.

There was a statistically significant association between DR and vitamin D deficiency with an overall pooled OR of 1.27 (95% CI, 1.17-1.37; P = 0.001; I² = 80%; P_{heterogeneity} = 0.01). There was also a statistically significant lower serum vitamin D level in patient subgroups with DR versus control groups, with an overall mean difference of -1.32 ng/mL (95% CI, -2.50 to -0.15; P = 0.001; I² = 89%; P_{heterogeneity} = 0.01).

There is a statistically significant association between vitamin D deficiency and DR.