To assess coexisting hypertension as a risk factor for diabetic retinopathy (DR) in type 2 diabetes mellitus.Design and Method:
A total of 977 type-2 diabetic patients recruited retrospectively in 2008 from Bangladesh Institute of Research and Rehabilitation in Diabetes, Endocrine and Metabolic Disorder (BIRDEM) based on hospital records for determining the incidence of diabetic retinopathy (DR), who were naive type-2 diabetes during 1993. At the end of 15 year follow-up 495 patients were diagnosed as DR by retinal colour photography. Data on diabetes and lipid profile with serum creatinine, blood pressure and biophysical measures were obtained at baseline, 5, 10 and 15 years follow-up. Binary logistic regression model was used to assess the associations of co-existing hypertension with retinopathy risk adjusting for clinical, biochemical and anthropometric variables.Results:
In all three follow-up points, including at baseline, mean systolic and diastolic blood pressure were found to significantly higher among patients who developed DR (P < .001). Binary logistic regression model confirmed coexisting hypertension (OR 3.2; 95% CI 2.2 -4.7) as a significant risk factor of DR adjusting for possible confounders; serum creatinine (OR 21.9; 95% CI 14.0 -35.4) and glycemic control status (OR 17.2; 95% CI 9.4 -31.4). Interaction between hypertension, glycemic control and raised serum creatinine did not appear to be statistically significant (P > 0.05).Conclusions:
Co-existing hypertension is a significant risk factor of DR irrespective of nephropathy or glycolic control status among Type 2 diabetes mellitus.