Elevated serum homocysteine, low serum vitamin B12, folate, and age-related macular degeneration: the Blue Mountains Eye Study.

Abstract

To assess associations between increased serum homocysteine, low vitamin B12, low folate, and age-related macular degeneration (AMD). Population-based, cross-sectional analysis. Serum homocysteine, vitamin B12, and folate were measured in 2,335 participants of the Blue Mountains Eye Study second survey. AMD detected from retinal photographs included atrophic or neovascular lesions. After adjusting for age, gender, and smoking in logistic regression models, homocysteine >15 micromol/l was associated with an increased likelihood of AMD in participants aged <75 years (odds ratio [OR] 3.21, 95% confidence interval [95% CI] 1.09 to 9.43). A similar association was found for vitamin B12 <125 pmol/l (OR 2.30, 95% CI 1.08 to 4.89) among all participants. In participants with homocysteine < or =15 micromol/l, low serum B12 was associated with nearly four-fold higher odds of AMD (OR 3.74, 95% CI 1.06 to 13.24). Folate was not statistically significantly associated with AMD. Increased homocysteine and low vitamin B12 were independently associated with an increased risk of AMD in this study population.