Study on Risk Factors Associated with Severity of Diabetic Retinopathy in Type-2 Diabetic Patients, Attending a Tertiary Care Centre in Kerala

Introduction: Diabetic retinopathy (DR) is a significant public health concern affecting individuals with diabetes mellitus (DM). Despite treatment advances, a substantial proportion of patients do not respond adequately. This study investigates risk factors associated with the progression of non-proliferative diabetic retinopathy (NPDR) to proliferative diabetic retinopathy (PDR) in type-2 diabetes patients. Methods: A retrospective case-control study was conducted on diabetic patients older than 40 years with at least 5 years of Type-2 Diabetes Mellitus history, attending ophthalmology clinic in Government Medical College, Thrissur, a tertiary care hospital. Data from patients with retinal examination showing diabetic retinopathy were analyzed. Records with missing data were excluded. Patients with Proliferative Diabetic Retinopathy (n=153) were compared with those having Non- Proliferative Diabetic Retinopathy (n=230). Various risk factors were assessed using statistical analysis. Results: Among the studied variables, sex, duration of diabetes, serum urea, serum creatinine, serum triglycerides, and chronic kidney disease were significantly different between Proliferative Diabetic Retinopathy and Non-Proliferative Diabetic Retinopathy patients. Binary logistic regression revealed that duration of diabetes (OR = 1.8, 95% CI = 1.1 - 2.39) and serum creatinine (OR =1.8, 95% CI = 1.1 - 2.39) independently influenced Proliferative Diabetic Retinopathy development. Conclusion: This study highlights that longer diabetes duration and elevated serum creatinine levels independently increase the risk of Non- Proliferative Diabetic Retinopathy progressing to Proliferative Diabetic Retinopathy in type-2 diabetic patients. Other factors such as age, gender, hyperlipidemia, systemic hypertension, type of diabetic treatment, and history of ischemic heart disease did not show significant associations with disease progression. These findings emphasize the importance of close monitoring, early detection, and intervention in patients with Non- Proliferative Diabetic Retinopathy, particularly those with a longer diabetic history, to prevent Proliferative Diabetic Retinopathy development. Further research should explore the causal relationship between serum creatinine and diabetic retinopathy progression and evaluate the impact of renal disease management on disease outcomes. Keywords: Diabetic Retinopathy, diabetes mellitus (DM), Type-2 Diabetes Mellitus (T2DM).