FEB 27, 2009
Comprehensive Ophthalmology, Retina/Vitreous
This randomized, double-blind, placebo-controlled trial of a large cohort of women at high risk of cardiovascular disease, finds that those who took a combination of B vitamins - B-6, folic acid and B-12 - reduced their risk of macular degeneration by more than one-third after seven years compared to controls.
There were 55 cases of AMD in the treatment group and 82 in the placebo group (relative risk, 0.66; 95% confidence interval, 0.47-0.93 [P = .02]). For visually significant AMD, there were 26 cases in the combination treatment group and 44 in the placebo group (relative risk, 0.59; 95% confidence interval, 0.36-0.95 [P = .03]).
Though B vitamins lower homocysteine, once thought to raise heart disease risk, the nutrients weren't helpful for that in the larger study on cardiovascular disease.
The authors theorize the eye's small blood vessels may respond better to B vitamins' effect on homocysteine than the body's large vessels.