Analysis of risk factors in the development of diabetic retinopathy

Assumed risk factors in the development of diabetic retinopathy were examined in 401 diabetic patients who had visited our clinic at regular intervals over 5 years. These subjects showed no funduscopic abnormalities at their first visit, whereas 114 out of 401 cases (28.4%) developed retinopathy within 5 years while 287 cases (71.6%) remained unaffected. 110 cases each were selected both from the affected and unaffected groups, matching in sex, age at onset and duration, and the frequencies of various risk factors were compared. In the affected and unaffected groups, the mean maximal body weight indexes were 125. 5 +/- 19.6% and 123.5 +/- 20.1%, respectively, but the number of subjects with excessive obesity (greater than or equal to 130%) was greater in the former than in the latter (p less than 0.05, chi 2-test). The number of patients with poor blood glucose control was greater in the former while that with good control was greater in the latter (p less than 0.05, chi 2-test). No differences were observed between the two groups for other parameters, including method of treatment. In conclusion, among the various risk factors examined, only obesity and poorer blood glucose control were significant contributors to the development of diabetic retinopathy.