Background: Reports have suggested relationships of body weight with age-related maculopathy (ARM), particularly its nonneovascular (dry) forms, but results are inconsistent and prospective data are scarce.
Objective: To examine prospectively relationships of body mass index (BMI; calculated as weight in kilograms divided by the square of height in meters) with visually significant dry and neovascular ARM during an average of 14.5 years of follow-up.
Methods: Incident ARM was assessed by medical record confirmation of self-reported ARM among the 21 121 men participating in the Physicians' Health Study who (1) were followed up for at least 7 years, (2) were free of visually significant ARM at baseline, and (3) had information on BMI and cigarette smoking. We used proportional hazards regression models to estimate rate ratios (RRs) and 95% confidence intervals (CIs) for visually significant dry ARM (256 cases) and neovascular ARM (84 cases) within 4 categories of BMI: lean (< 22.0), normal (22.0-24.9), overweight (25.0-29.9), and obese (> or = 30.0).
Results: Adjusting for age, randomized aspirin and beta carotene assignments, and cigarette smoking, the incidence for visually significant dry ARM was lowest in men with a normal BMI. Compared with these men, the RRs (95% CIs) were as follows: 1.43 (1.01-2.04) for lean, 1.24 (0.93-1.66) for overweight, and 2.15 (1.35-3.45) for obese men. Although there was no significant relationship of BMI with the diagnosis of neovascular ARM, due to the small number of cases these analyses could not rule out an important relationship.
Conclusions: Obesity is a risk factor for visually significant ARM in men, in particular for dry ARM. However, the relationship of BMI with dry ARM appears to be J-shaped, and the leanest individuals also appear to be at increased risk.