Tehran University Medical Journal

Background: Diabetes is a chronic non-communicable disease with increasing prevalence. Retinopathy is one of the main complications of diabetes. Early diagnosis and treatment of retinopathy can reduce the risk of low vision and blindness. The aim of this study was to apply regression analysis of current status data to determine risk factors of diabetic retinopathy in patients with type 2 diabetes being referred to the Ophthalmology Clinic of Yazd Diabetes Research Center, Iran.

Methods: In this analytical-observational study, 459 patients with type 2 diabetes were enrolled in the study and the ophthalmic examinations done by an ophthalmologist included visual acuity, intraocular pressure (IOP) measurement and slit-lamp examination. After pupil dilatation, funduscopy was done and the patients were classified according to ETDRS criteria. A proportional hazard model for current status data was used to identify the risk factors for retinopathy.

Results: The hazard rate of having retinopathy increased by 5% for an increase of one year in the duration of diabetes (p<0.05) and the hazard rate of having retinopathy was 1.1 times greater in patients who had used insulin for diabetes compared with other type 2 diabetes patients (p<0.05).

Conclusion: This study showed that a history of hypertension may reduce the risks of diabetic retinopathy. In patients with the early diagnosis of diabetes, regular examination of the fundus, blood sugar control and tight control of high blood pressure are recommended.