772Received August 1, 2016Accepted for publication August 29, 2016J Nutr Health AgingVolume 21, Number 7, 2017IntroductionClinical trial data has shown that nutrients with antioxidant and anti-inflammatory properties (vitamins C, E, beta-carotene and zinc) protect against progression of age-related macular degeneration (AMD) from early to late disease (1). More remains to be learned about the influence of other nutrients, such as vitamin D, which has been hypothesized to reduce risk of AMD (2) because of its immune modulating, anti-inflammatory (3-5), and anti-angiogenic properties (6); however it is relatively understudied with respect to AMD in cohort studies, particularly those with racial diversity. Existing literature supports a protective association between prevalent AMD, either early or late, and vitamin D status, assessed with the blood biomarker 25-hydroxyvitamin D [25(OH)D] reflecting sunlight exposure as well as intake from foods and supplements (2, 7-10). However, not all studies support this association (11-14). Only three previous studies were conducted in racially/ethnically diverse samples, inclusive of non-Hispanic whites (2, 12), non-Hispanic blacks (2, 12), Mexican Americans (2), and Koreans (9), limiting our understanding of this association in racial/ethnic groups such as African Americans, who have one of the highest burdens of vitamin D deficiency (15). The 2011 Institute of Medicine’s (IOM) report on the Dietary Reference Intakes (16) of vitamin D and calcium only supports a role for vitamin D in bone health stating not enough scientific evidence exists to make conclusions on vitamin D status in relation to other health VITAMIN D STATUS AND PREVALENT EARLY AGE-RELATED MACULAR DEGENERATION IN AFRICAN AMERICANS AND CAUCASIANS: THE ATHEROSCLEROSIS RISK IN COMMUNITIES (ARIC) STUDY A.E. MILLEN 1 , J. NIE 1 , M.W. SAHLI 2 , J.A. MARES 3 , K.J. MEYERS 3 , B.E.K. KLEIN 3 , M.J. LAMONTE 1 , P.L. LUTSEY 4 , C.A. ANDREWS 5 , R. KLEIN 31. Department of Epidemiology and Environmental Health , School of Public Health and Health Professions, University at Buffalo, The State University of New York, Buffalo, NY, USA; 2. Department of Public Health and Health Sciences, School of Health Professions and Studies, University of Michigan-Flint Flint, MI, USA; 3. Department of Ophthalmology and Visual Sciences, School of Medicine and Public Health, The University of Wisconsin-Madison, Madison, WI, USA; 4. Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN; 5. Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, MI, USA. Corresponding author: Amy E. Millen, Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo, The State University of New York, 270 Farber Hall, Buffalo, NY 14214-8001. Telephone: (716) 829-5377, Fax: (716) 829-2979, aemillen@buffalo.edu Abstract: Objectives: Vitamin D status has been hypothesized to protect against development of early age-related macular degeneration (AMD) via its anti-inflammatory properties and its possible beneficial influence on blood pressure control. We investigated the association between vitamin D status and prevalent early AMD in a community-based cohort. Design: This was a cross-sectional study. Setting: This was a secondary data analysis of already existing data from the Atherosclerosis Risk in Communities Study (ARIC) cohort collected from 1990 to 1995. Participants: There were 9,734 (7,779 Caucasians, 1,955 African American) ARIC participants (aged 46 to 70 at visit 2 [1990-1992]) with 25(OH)D data available at visit 2, AMD assessment at visit 3 (1993-1995), and complete covariate data. Measurements: Vitamin D status was assessed with serum 25-hydroxyvitamin D (25(OH)D) concentrations from bloods drawn at visit 2. Prevalent, early AMD (n=511) was assessed at visit 3 (1993-95) with nonmydriatic retinal photographs of one randomly chosen eye. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for early AMD by categories of 25(OH)D in nmol/L (deficient <30, inadequate 30-<50, and two categories of adequate status: 50-<75 and ≥75). Linear trend was estimated using continuous 25(OH)D concentrations. ORs were adjusted for age, race, and smoking status. We further adjusted for hypertension status to examine if vitamin D status influenced early AMD via its effects on blood pressure. Exploratory analyses of effect modification by age, sex, race and high risk genotypes [Y402H complement factor H (CFH) rs1061170 and the A69S age-related maculopathy susceptibility 2 (ARMS2) rs10490924 polymorphisms] were conducted. Results: The prevalence of early AMD was 5%, and 5% of participants were vitamin D deficient. The adjusted OR (95% CIs) for early AMD among those with adequate (≥75 nmol/L) compared to deficient (<30 nmol/L) vitamin D status was 0.94 (0.59-1.50), p-trend=0.86. Further adjustment for hypertension status did not influence results (OR [95% CI]=0.95 [0.59-1.52], p-trend=0.84). Results did not vary significantly by age, race, sex, early AMD subtype (soft drusen or retinal pigment epithelium depigmentation), or ARMS2 genotype. Results did not vary significantly by CFH genotype in African Americans. The p for multiplicative interaction between 25(OH)D and CFH genotype was 0.06 in Caucasians, but OR [95% CIs] for AMD by vitamin D status were similar in each CFH genotype and not statistically significant.Conclusions: Vitamin D status was not associated with early AMD in this cohort sample. Key words: Vitamin D, 25-hydroxyvitamin D, macular degeneration, retinal diseases, epidemiology, cohort studies.
