Five-year incidence and progression of vascular retinopathy in persons without diabetes: the Blue Mountains Eye Study

Abstract

Purpose: To assess the 5-year incidence of vascular retinopathy and its associations in an older nondiabetic population.

Methods: The Blue Mountains Eye Study examined 3654 residents aged 49+ years (82.4% response rate) during 1992-1994, and re-examined 2335 (75.1% of survivors) during 1997-1999. Retinopathy lesions (microaneurysms, haemorrhages, hard or soft exudates) were assessed from 6-field retinal photographs in persons without diabetes. Incident retinopathy was assessed in those at risk. Hypertensive status was defined following the WHO/International Society of Hypertension guidelines.

Results: Of the 2335 re-examined, 195 had retinopathy lesions at baseline and 1725 were at risk of retinopathy after excluding subjects with diabetes (n=261), retinal vein occlusion (n=52) or missing/un-gradable photographs (n=102). The cumulative 5-year incidence was 9.7% (95% confidence intervals (CI) 8.3-11.1%). Age was the only factor significantly associated with incident retinopathy (Pfor trend=0.012). Neither fasting blood glucose (age-sex-adjusted P=0.147) nor hypertension (adjusted Pfor trend=0.43) was associated with incident retinopathy. Of the 195 with retinopathy lesions at baseline, 3.5% developed diabetes, 13.3% progressed, and 72.3% regressed/disappeared over 5 years. Progression was positively associated with elevated blood pressure (BP) (adjusted odds ratio (OR) 1.3, 95% CI 1.1-1.6 per 10 mmHg systolic BP) and inversely associated with fasting glucose level (OR 0.36, CI 0.14-0.92 per mmol/l increase). Aspirin use was weakly associated with regression (OR 2.4, CI 1.0-6.0).

Conclusions: Over 5 years, retinopathy developed in 10% of older people without diabetes, while 72% of baseline lesions regressed. Age was significantly associated with the development of these lesions.