Cardiovascular Risk Factors and the Long-term Incidence of Age-Related Macular Degeneration: The Blue Mountains Eye Study

Abstract

To assess the relationship between cardiovascular disease and cardiovascular risk factors, other than smoking, and risk of long-term incident age-related macular degeneration (AMD). Population-based cohort study. There were 3654 baseline (1992-1994) participants aged > or = 49 years included in the Blue Mountains region, west of Sydney, Australia. Of these, 2335 (75% of survivors) were reexamined after 5 years (1997-1999) and 1952 (76% of survivors) after 10 years (2002-2004). Stereoscopic color fundus photographs were graded using the Wisconsin Age-related Maculopathy Grading System. History, physical examination, and fasting blood samples provided data on possible risk factors. Age-related macular degeneration incidence was calculated using the Kaplan-Meier survival approach. Discrete linear logistic models were used to assess risk of incident AMD. Relative risks (RR) and 95% confidence intervals (CI) are presented after adjusting for age, gender, smoking, and other risk factors. Incident early and late AMD. Increasing high-density lipoprotein (HDL) cholesterol was inversely related to incident late AMD (RR per standard deviation [SD] increase, 0.74; 95% CI, 0.56-0.99). Elevated total/HDL cholesterol ratio predicted late AMD (RR per SD increase, 1.35; 95% CI, 1.07-1.70) and geographic atrophy (GA; RR per SD, 1.63; 95% CI, 1.18-2.25). Diabetes predicted incident GA (RR, 3.89; 95% CI, 1.36-11.08), but not neovascular AMD. History of stroke (RR 2.01; 95% CI, 1.12-3.58), or any cardiovascular disease (stroke, myocardial infarction, or angina; RR, 1.57; 95% CI, 1.13-2.16) predicted incident early AMD and incident indistinct soft or reticular drusen (RR, 2.38; 95% CI, 1.33-4.27 for stroke; RR, 1.80; 95% CI, 1.28-2.52 for any cardiovascular disease). Neither pulse pressure, systolic or diastolic blood pressure, or presence of hypertension at baseline were associated with incident AMD. Our findings provide some evidence of links between cardiovascular risk factors and AMD. Further prospective evaluation of these relationships is warranted, as these findings could have therapeutic implications.