Vitamin D Levels in Patients with Noninfectious Uveitis: A Systematic Review and Meta-Analysis.

Purpose: Vitamin D deficiency has been associated with higher rates of autoimmune disease, including noninfectious uveitis. This PRISMA-compliant review and meta-analysis aimed to analyze the correlation between noninfectious uveitis and vitamin D levels.

Methods: We searched PubMed, Embase, Cochrane, and Web of Science databases for studies, published in English, assessing vitamin D levels in patients diagnosed with noninfectious uveitis. The outcomes of interest were vitamin D deficiency, vitamin D mean level, vitamin D supplementation, and smoking rates. A subgroup analysis of inactive uveitis and active uveitis was performed. The heterogeneity was assessed with Cochrane Q-test and I statistics;  > 0.10 and I > 50% were considered significant for heterogeneity. Statistical analysis was conducted using Review Manager 5.3.

Results: 9 studies were included in the meta-analysis comprising a total of 10 711 patients, of whom 1,368 were diagnosed with noninfectious uveitis. Patients with noninfectious uveitis had worse results regarding vitamin D deficiency when compared with the control group (OR 0.58; CI 95% 0.44 to 0.77;  = 0.0002; I = 61%). Patients with inactive uveitis had better results towards vitamin D deficiency when compared with active uveitis (OR 5.00; CI 95% 2.84 to 8.81;  < 0.001; I = 0%).

Conclusion: Our research supports the increasing evidence that associates vitamin D deficiency with noninfectious uveitis and its activity. Further investigation into the efficacy of vitamin D screening and supplementation in reducing the recurrence of uveitis is necessary.