To examine the association of sunlight exposure and indicators of sunsensitivity with the 10-year incidence of age-related maculopathy (ARM).
Population-based cohort study.
We included persons aged 43 to 86 years at the baseline examinationfrom 1988 to 1990, living in Beaver Dam, Wis, of whom 3684 persons underwent5-year follow-up and 2764 underwent 10-year follow-up.
Data on sun exposure and indicators of sun sensitivity were obtainedfrom a standardized questionnaire administered at baseline and/or follow-up.We determined ARM status by grading stereoscopic color fundus photographsusing the Wisconsin Age-Related Maculopathy Grading System.
Main Outcome Measures
Incidence and progression of ARM.
While controlling for age and sex, we found that participants exposedto the summer sun for more than 5 hours a day during their teens, in their30s, and at the baseline examination were at a higher risk of developing increasedretinal pigment (risk ratio [RR], 3.17; 95% confidence interval [CI], 1.24-8.11; P = .01) and early ARM (RR, 2.14; 95% CI, 0.99-4.61; P = .05) by 10 years than those exposed less than 2 hoursper day during the same periods. In participants reporting the highest summersun exposure levels in their teens and 30s, the use of hats and sunglassesat least half the time during the same periods was associated with a decreasedrisk of developing soft indistinct drusen (RR, 0.55; 95% CI, 0.33-0.90; P = .02) and retinal pigment epithelial depigmentation(RR, 0.51; 95% CI, 0.29-0.91; P = .02). Participantswho experienced more than 10 severe sunburns during their youth were morelikely than those who experienced 1 or no burn to develop drusen with a 250-µmdiameter or larger (RR, 2.52; 95% CI, 1.29-1.71; P =.01) by the 10-year examination. No relationships were found between UV-Bexposure, winter leisure time spent outdoors, skin sun sensitivity, or numberof bad sunburns experienced by the time of the baseline examination and the10-year incidence and progression of ARM or its associated lesions.
Few significant relationships between environmental exposure to lightand the 10-year incidence and progression of ARM were found in the BeaverDam Eye Study. Consistent with results from the baseline and 5-year follow-upexaminations, significant associations were found between extended exposureto the summer sun and the 10-year incidence of early ARM and increased retinalpigment. A protective effect of hat and sunglasses use by participants whilein their teens and 30s against the 10-year incidence of soft indistinct drusenand retinal pigment epithelial depigmentation was also found, but only inthose who reported the highest amount of sun exposure during the same periods.