Retinopathy predicts cardiovascular mortality in type 2 diabetic men and women

To investigate the association of retinopathy with the risk of all-cause, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality in type 2 diabetic subjects in a population-based 18-year follow-up study with particular emphasis on sex differences.

Our study cohort comprised 425 Finnish type 2 diabetic men and 399 type 2 diabetic women who were free of CVD at baseline. The findings were classified based on standardized clinical ophthalmoscopy to categories of no retinopathy, background retinopathy, and proliferative retinopathy. The study end points were all-cause, CVD, and CHD mortality.

Adjusted Cox model hazard ratios (95% CIs) of all-cause, CVD, and CHD mortality in men were 1.34 (0.98-1.83), 1.30 (0.86-1.96), and 1.18 (0.74-1.89), respectively, for background retinopathy and 3.05 (1.70-5.45), 3.32 (1.61-6.78), and 2.54 (1.07-6.04), respectively, for proliferative retinopathy and in women 1.61 (1.17-2.22), 1.71 (1.17-2.51), and 1.79 (1.13-2.85), respectively, for background retinopathy and 2.92 (1.41-6.06), 3.17 (1.38-7.30), and 4.98 (2.06-12.06), respectively, for proliferative retinopathy.

Proliferative retinopathy in both sexes and background retinopathy in women predicted all-cause, CVD, and CHD death. These associations were independent of current smoking, hypertension, total cholesterol, HDL cholesterol, glycemic control of diabetes, duration of diabetes, and proteinuria. This suggests the presence of common background pathways for diabetic microvascular and macrovascular disease other than those included in the conventional risk assessment of CVD. The sex difference observed in the association of background retinopathy with macrovascular disease warrants closer examination.