A large population-based study has found that the 5-year risk of age-related macular degeneration is declining by birth cohort.

The study, published in the November issue of JAMA Ophthalmology, found that in the 4819 Wisconsin-based study participants the incidence of AMD drastically declined each generation. When adjusting for age and sex, each generation was 60% less likely to develop AMD compared to the generation previous. The 5-year age-adjusted risk for the Greatest Generation (people born 1901-1924) was 8.8%, for the Silent Generation (born 1925-1945) 3.3%, and for Baby Boomers (1946-1964) just 1.0%. The age-adjusted 5-year risk for Generation X (born 1965-1984) was just 0.3%. The decline in risk remained significant even when controlling for known AMD-risk factors such as smoking and cholesterol level.

The study authors admit that the factors explaining this decline in risk are not known, though they point out that this is consistent with a decline in risk of dementia and cardiovascular disease. All three of these diseases involve vascular and inflammatory pathways.

The study authors put forth as possible reasons for the decline: cleaner air and water, access to vaccines and antibiotics, fewer childhood infectious diseases and improved maternal health and childhood nutrition.

These results suggest that “the Baby Boom generation may avoid the loss of vision due to AMD that has been a major source of disability for prior generations.”

The full study is available at https://jamanetwork.com/journals/jamaophthalmology/fullarticle/2663390