Better adherence to a Mediterranean diet reduces the risk of developing neovascular age-related macular degeneration (nvAMD), according to a study published onlineNovember 5 in Ophthalmology.
“The MDS [Mediterranean Diet Score] has been inversely associated with cardiovascular disease, cancer, and mortality, and more recently progression to advanced AMD,” write Ruth E. Hogg, PhD, from Queen’s University Belfast, United Kingdom, and colleagues. “Our current findings provide further evidence for the potential value of adhering to this diet on eye health.”
The researchers evaluated 5060 patients aged 65 years or older, chosen randomly from centers in Norway, Estonia, the United Kingdom, France, Italy, Greece, and Spain between 2001 and 2002. Dietary intake during the previous 12 months was evaluated and scored using the MDS, which captured information about consumption of items such as olive oil, fish, wine, fruit, legumes, and meat/meat products. All patients underwent eye examinations, including digital retinal photographs, and blood samples were collected to evaluate antioxidant levels including lutein, zeaxanthin, carotene, and lycopene. In addition, information was collected regarding smoking and alcohol use and environmental exposure.
The mean age among participants was 73.6 years, and 55% were women. Eye exams found that 109 participants had nvAMD, 49 had geographic atrophy, 2333 had early AMD, 641 had large drusen, and 2262 showed no signs of AMD.
The authors note, however, that there was no association between MDS and early-stage AMD (grades 1 – 3; P trend = .9). They do acknowledge that, because the study was carried out before the routine use of optical coherence tomography, early AMD changes may have been misclassified.
Fundic images were reviewed at a single center and categorized by grade, where grade 0 was the least severe and grade 4 was the most severe, with serous or hemorrhagic retinal or retinal pigment epithelial detachment, subretinal neovascular membrane, periretinal fibrous scar, or geographic atrophy.
The authors acknowledge that no causal inferences can be made regarding these associations, given the cross-sectional nature of the study. In addition, they note that self-reporting of dietary information may also lead to bias.
Noting that the MDS is a useful tool to characterize dietary patterns, “[i]nterventions to encourage the adoption of the Mediterranean diet should be developed more widely, and methods by which such behavior change can be achieved and maintained over the long term should be investigated,” conclude Dr Hogg and colleagues.