Serum 25-Hydroxyvitamin D Concentrations and Incidence of Age-Related Macular Degeneration: The Atherosclerosis Risk in Communities Study.

Purpose: To investigate the association between serum 25-hydroxyvitamin D (25[OH]D) concentrations at visit 2 (1990-1992) and the 18-year incidence of age-related macular degeneration (AMD) between visit 3 (1993-1995) and visit 5 (2011-2013). Methods: This prospective analysis was conducted in a subset of participants (n = 1225) from the Atherosclerosis Risk in Communities Study. We evaluated the incidence of any, early, and late AMD from visit 3 to 5. The 25(OH)D concentrations were assessed in 2012-2013 by using stored serum from visit 2. Retinal fundus photographs taken at both visits were graded side by side to determine the incidence of AMD. Logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for incident AMD outcomes during 18 years of follow-up (1993-1995 to 2011-2013) by tertile of 25(OH)D adjusted for age, race, and smoking status. P for linear trend was estimated by using continuous 25(OH)D concentrations. Sensitivity analyses applied inverse probability weights to account for selection to have eye photographs, death, and loss to follow-up. Results: There was a decreased odds of any incident AMD (n = 139) and large, soft drusen (n = 80) in 25(OH)D tertile 3 versus 1, with OR (95% CI) = 0.57 (0.36-0.90), P trend = 0.11 and with 0.52 (0.28-0.93), P trend = 0.18, respectively. Applying sampling weights attenuated these results to 0.66 (0.38-1.16), P trend = 0.32 (any incident AMD) and 0.54 (0.27-1.09), P trend = 0.36 (large, soft drusen), respectively, suggesting these associations may be biased by loss to follow-up and sampling for retinal photographs at visit 5. No statistically significant results were observed with pigmentary abnormalities (n = 46) or incident late AMD (n = 26). Conclusions: High 25(OH)D concentrations, approximately >70 nM, may be associated with decreased odds of incident early AMD.