Vitamin D may play a significant role in eye health, specifically in the possible prevention of age-related macular degeneration (AMD) among women who are more genetically prone to developing the sight-damaging disease, according to a finding reported by the University at Buffalo.
Associate Professor Amy Millen from University at Buffalo School of Public Health and Health Professions found women who are deficient in vitamin D and have a specific high-risk genotype are 6.7 times more likely to develop AMD than women with sufficient vitamin D status and no high risk genotype.
“This is not a study that can, alone, prove a causal association, but it does suggest that if you’re at high genetic risk for AMD, having a sufficient vitamin D status might help reduce your risk,” said Assoc. Prof. Millen.
“To our knowledge, this is the first study that’s looked at the interaction between genetic risk and vitamin D status in the context of age-related eye disease.”
Vitamin D shows promise for protecting… because of its anti-inflammatory and antiangiogenic properties…
Researchers analysed data compiled on 1,230 women ages 54 to 74 who participated in the Carotenoids in Age-related Eye Disease Study (CAREDS).
“Macular degeneration has been found to be strongly associated with genetic risk,” Millen says. Among many genes linked to AMD, one of the strongest is a specific genetic variant (Y402H) in the complement factor H gene, called CFH for short. This gene codes for the CFH protein that is involved in the body’s immune response to destroy bacteria and viruses.
Inflammation is believed to be involved in the development of macular degeneration.
“People who have early stage AMD develop drusen, lipid and protein deposits that build up in the eye. Your body sees this drusen as a foreign substance and attacks it, in part via the complement cascade response,” said Assoc. Prof. Millen. “CFH is one of the proteins involved in this response. We see more AMD in people who have certain variants in the gene which encodes a form of this CFH protein that is associated with a more aggressive immune response.”
Vitamin D shows promise for protecting against macular degeneration because of its anti-inflammatory and antiangiogenic properties; antiangiogenic refers to slowing the growth of new blood vessels, often seen in late stages of AMD.
“Our study suggests that being deficient for vitamin D may increase one’s risk for AMD, and that this increased risk may be most profound in those with the highest genetic risk for this specific variant in the CFH protein… Our message is not that achieving really high levels of vitamin D are good for the eye, but that having deficient vitamin D levels may be unhealthy for your eyes… Although the odds of having AMD were higher in women who were deficient for vitamin D, with 25(OH)D levels below 12 ng/mL (30 nmol/L), increasing vitamin D levels beyond 12 ng/mL did not further lower the odds of AMD to any meaningful extent,” she said.
A/Prof. Millen said that until now there has not been enough evidence to make any recommendation based on D status and other outcomes beyond bone health.”
