Abstract
Abstract: :
Purpose:To assess the relationship between smoking and baseline cardiovascular risk factors and the 10–year incidence of age–related maculopathy (ARM) in an older Australian cohort. Methods: Of 3654 participants aged 49+ years examined during 1992–4 (baseline), 2335 (75% of 3111 survivors) were re–examined at 5–year (1997–9) and 1935 (75.0% of 2581 survivors) at 10–year (2002–4) exams. Photographic grading used the Wisconsin System. Incident late and early ARM cases included participants free of these signs at baseline but who developed maculopathy at either the 5– or 10–year exams. Baseline cardiovascular factors assessed included current smoking, past history of hypertension, diabetes, angina, heart attack or stroke plus measurements of systolic and diastolic blood pressure, pulse pressure, fasting blood lipids and glucose. Results: Of 2581 surviving baseline participants, 1935 (75.0 %) were re–examined in the 10–year follow up. After exclusions, 1559 with gradable retinal photographs were considered at risk of progression. We also included a further 731 persons seen at 5–year exams but not at the 10–year exams. Incident late ARM developed in 55 persons (2.4%) and incident early ARM developed in 285/ 2112 participants (13.5%). Incident late and early ARM were both strongly related to increasing age (p for trend <0.0001). Participants who were current smokers at the baseline exam had more than twice the risk of developing late ARM over the 10–year period, age–sex–adjusted odds ratio (OR) 2.2, 95% confidence interval (CI) 1.1–4.8 than past– or never–smokers. Current smokers also developed late ARM at an average 8 years younger age than past– or never–smokers (mean age 65.7 years for current smokers vs 73.9 years for non–smokers). Participants giving a history of stroke were found to have a higher risk of developing early ARM (OR 1.9, CI 1.1–3.4), but this was not significant for incident late ARM (OR 1.8, CI 0.6–5.1). Neither systolic, diastolic or pulse pressure was significantly associated with incident late or early ARM. We could not detect any significant associations between other baseline cardiovascular risk factors and incident ARM. Conclusions: These data confirm smoking as the principal environmental risk factor for ARM. Our 10–year data could not confirm the cardiovascular–ARM associations suggested in the Beaver Dam Eye Study 10–year report.
Keywords: age-related macular degeneration • choroid: neovascularization • clinical (human) or epidemiologic studies: prevalence/incidence