Risk indicators of diabetic retinopathy in patients with type 2 diabetes screened by fundus photographs: a study from Pakistan

This study aims to evaluate the risk indicators of diabetic retinopathy in patients with type 2 diabetes screened by fundus photographs at a tertiary care diabetes centre in Karachi, Pakistan. A cross-sectional study was conducted at the outpatient department of Baqai Institute of Diabetology and Endocrinology from October 2009 to March 2010. Patients ≥30 years of age were recruited randomly. Demographic, anthropometric, clinical and biochemical data were collected, and ophthalmic screening was done by two field fundus photography. Fundus photographs of 366 patients were graded according to the modified Early Treatment Diabetic Retinopathy Disease Severity Scale (ETDRS) criteria. Retinopathy was present in 27.3 % patients. Fifteen percent of patients had non-sight-threatening retinopathy while 12 % had sight-threatening retinopathy. Patients with retinopathy had significantly increased mean duration of diabetes, systolic and diastolic blood pressure and HbA1c (p < 0.001). Patients with sight-threatening retinopathy also had increased serum cholesterol (p < 0.05) and serum creatinine (p < 0.001). Multivariate logistic regression revealed male gender (3.5 times, 95 % confidence interval (CI); 1.73–7.12), increased duration of diabetes (≥10 years, 5.46 times, 95 % CI; 2.15–13.85), hypertension (≥130/85, 1.96 times, 95 % CI; 0.95–4.03) and poor glycemic control (HbA1c ≥7 %, 1.39 times, CI; 1.23–1.56) as significant factors for developing retinopathy. Diabetic retinopathy was present in every fourth subject, while sight-threatening retinopathy was present in every eighth subject with type 2 diabetes. The results of the present study highlight the importance of screening for retinopathy. The identification of risk indicators associated with retinopathy in our population may lead to measures of prevention of sight-threatening complication of diabetes. Fundus photographs revealed increased frequency of retinopathy among patients with type II diabetes. Male gender, increased mean duration of diabetes, hypertension and poor glycemic control related with the presence of retinopathy, while increased serum cholesterol and creatinine related with severity of retinopathy. The present study highlights the importance of screening for retinopathy. The presence and severity of retinopathy in this population was attributed to the factors identified in earlier studies. The present study thus validated the findings of studies conducted on diverse populations across the world.