Abstract
Purpose: :
To describe the relationship between measures of physical activity and the 15–year cumulative incidence of Age–Related Maculopathy (ARM).
Methods: :
Included 4,926 persons, 43–86 years of age at the time of a baseline examination in 1988–1990, living in Beaver Dam, Wisconsin, of whom 3,684 participated in a 5–year follow–up examination 2,764 participated in a 10–year follow–up, and 2,119 participated in a 15–year follow–up. Characteristics of drusen and other lesions typical of ARM were determined by grading stereoscopic color fundus photographs using the Wisconsin Age–Related Maculopathy Grading System. Measures of physical activity were obtained through a questionnaire administered at the baseline examination.
Results: :
The 15–year cumulative incidence of both early and late signs of ARM was higher in persons with a sedentary lifestyle (exercise < 3 times per week) and lower in persons walking more than 4 blocks or climbing more than 3 flights of stairs a day. After controlling for age, persons with a sedentary lifestyle were more likely to develop exudative ARM [hazard ratio (HR), 95% confidence interval (CI): 3.4 (1.4, 7.9) p<0.01]. This was consistent, but not statistically significant for early ARM [HR, CI: 1.3 (1.0, 1.6) p=0.08]. The incidence of pure geographic atrophy was not increased in persons with a sedentary lifestyle. After controlling for age, persons who climbed more flights of stairs were less likely to develop early ARM [HR per increasing category, CI: 0.90 (0.81, 0.99) p=0.04]. Stair climbing was not related to the incidence of late ARM. After controlling for age, increasing categories of the number of blocks walked per day was inversely related to exudative ARM [HR per increasing category, CI: 0.70 (0.54, 0.90) p<0.01]. Walking was not related to the incidence of early ARM or pure geographic atrophy. These results remained significant after further controlling for gender, history of arthritis, systolic blood pressure, body mass index, smoking and education (data not shown).
Conclusions: :
These data show a protective effect of physical activity for some signs of incident ARM, independent of body mass index and other comorbidity. These data suggest a possible modifiable behavior that might be protective against ARM.
Keywords: age-related macular degeneration • clinical (human) or epidemiologic studies: risk factor assessment