Long-term exposure to solar ultraviolet radiation as risk factor for age-related macular degeneration

A clinical epidemiological study has been conducted as a part of research project investigating chronic exposure to solar ultraviolet radiation (UVR) as a factor contributing of the onset of age related macular degeneration (ARMD). A clinical study included 632 subjects older than 50 from two different geographic areas, one with high solar radiation (the island of Solta) and the other (the Zagreb suburbs) with low solar radiation. Individual exposure to UVR was assessed to global exposure to sunlight, on the bases of detailed history of life-long exposure to sunlight, with special reference to professional history and geographysical specificities of the respective area. Fundus photographs were taken and fluorescein angiography were done. Statistically significant association was found between ARMD and mean daily exposure to solar radiation in region I - the island of Solta (chi-square 186,22; p=0.0000) and in region 2 the Zagreb suburbs (chi-square 25,66; p=0.0000) and in both regions together (chi-square = 216,43; p=0.0000). ARMD is more frequent in the subjects in the region I and with same exposure to sunlight (eight hours or more), what shows in favor of more UVR exposure. The results support an association between sunlight (especially UV and short-wave length visible light) and increased risk of ARMD.