Diabetic retinopathy is associated with an increased incidence of cardiovascular events in Type 2 diabetic patients

Abstract

We investigated the association of diabetic retinopathy with the risk of incident cardiovascular disease (CVD) events in a large cohort of Type 2 diabetic adults. Our study cohort comprised 2103 Type 2 diabetic outpatients who were free of diagnosed CVD at baseline. Retinal findings were classified based on fundoscopy (by a single ophthalmologist) to categories of no retinopathy, non-proliferative retinopathy and proliferative/laser-treated retinopathy. Outcomes measures were incident CVD events (i.e. non-fatal myocardial infarction, non-fatal ischaemic stroke, coronary revascularization procedures or cardiovascular death). During approximately 7 years of follow-up, 406 participants subsequently developed incident CVD events, whereas 1697 participants remained free of diagnosed CVD. After adjustment for age, body mass index, waist circumference, smoking, lipids, glycated haemoglobin, diabetes duration and medications use, patients with non-proliferative or proliferative/laser-treated retinopathy had a greater risk (P < 0.001 for all) of incident CVD events than those without retinopathy [hazard ratio 1.61 (95% confidence interval 1.2-2.6) and 3.75 (2.0-7.4) for men, and 1.67 (1.3-2.8) and 3.81 (2.2-7.3) for women, respectively]. After additional adjustment for hypertension and advanced nephropathy (defined as overt proteinuria and/or estimated glomerular filtration rate < or = 60 ml/min/1.73 m(2)), the risk of incident CVD remained markedly increased in those with proliferative/laser-treated retinopathy [hazard ratio 2.08 (1.02-3.7) for men and 2.41 (1.05-3.9) for women], but not in those with non-proliferative retinopathy. Diabetic retinopathy (especially in its more advanced stages) is associated with an increased CVD incidence independent of other known cardiovascular risk factors.