PROGRESSION OF RETINOPATHY IS RELATED TO GLYCEMIC CONTROL EVEN IN PATIENTS WITH MILD DIABETES-MELLITUS

To study the progression of retinopathy in patients with mild diabetes mellitus, we examined, in a cohort study, 347 patients treated with d iet alone at baseline. The patients participated in an ophthalmologica l screening and control programme, and diet-treated patients who were examined between January 1990 and July 1992 were included in the study and followed until October 1995. Mean follow-up time was 3.4 +/- 1.1 years. The alternative classification of the Wisconsin study was used to classify retinopathy, and the mean HbA(1c) values for the study per iod, to estimate the level of glycaemic control. At baseline, 314 of t he patients (90.5%) had no retinopathy, and 33 (9.5%) had mild non-pro liferative diabetic retinopathy. In 296 patients there was no retinopa thy progression, in 27 patients there was progression by 1 level in th e retinopathy scale, and in 24 patients by 2 levels or more. In 2 pati ents there was progression to proliferative diabetic retinopathy. The mean HbA(1c) (%) was 6.5 +/- 1.3. Higher HbA(1c) correlated to increas ed progression (r = 0.16; p = 0.005), and in a multivariate analysis, HbA(1c) remained associated with a progression of retinopathy by 2 lev els or more, with a relative risk of 1.4 per percent increase in HbA(1 c) (95% CI 1.1-2.0; p = 0.02). Furthermore, the presence of any retino pathy at baseline was associated with progression with a relative risk of 1.7 (95% confidence interval 1.1-2.8; p = 0.02). These data indica te that even slightly elevated levels of HbA(1c) might be associated w ith a risk of retinopathy progression.