Risk factors for age-related macular degeneration.

There is an increasing body of evidence as to the risk factors for age-related macular degeneration. Age and genetic make-up are the most important risk factors identified to date. Over the next decade, the different genes that are involved in the development of age-related macular degeneration will be identified. There is reasonably consistent evidence that smoking cigarettes results in increased risk of the disease. The question as to whether antioxidant vitamin and mineral supplementation prevents or delays the development of the disease will be resolved as the results of large ongoing trials become available in the next few years. Currently, there is conflicting evidence as to their benefits and some indication as to possible harm. Other risk factors such as alcohol consumption, oestrogen replacement and lifetime light exposure require further study. The study of the epidemiology of age-related macular degeneration would be facilitated by a greater standardization of methods. Studies with large numbers of late stage disease are needed in order to provide the power to investigate moderate risks. This may either be achieved by adding on macular degeneration studies to large cohort studies already in place, or by pooling data from smaller studies.