Prevalence and predictors of diabetic retinopathy with special emphasis on high uric acid among type 2 diabetic patients

Background: Diabetic retinopathy is the most common microvascular complication of diabetes. It is leading cause of preventable blindness in all age-groups and put a significant burden on health services. Evidence suggests the role of uric acid in diabetic retinopathy. Objectives: To estimate the prevalence and define the risk factors, particularly high serum uric acid of diabetic retinopathy among type 2 diabetic patients.
Methods: This is a retrospective cross sectional study performed on type 2 diabetic patients at the University Diabetes Center, King Abdul-Aziz University Hospital, Riyadh, Saudi Arabia, and the laboratory work was done at Strategic Center for Diabetes Research, King Saud University. Results: The study included 433 type 2 diabetic patients. Most of them (78.5%) aged over 50 years. Females represent 56.1% of the patients. The prevalence of diabetic retinopathy was 47.3%. Multivariate logistic regression analysis revealed that compared to patients aged 50 years or less, those aged more than 50 years were at 55% less risk to develop DR (Adjusted odds ratio “AOR”=0.45; 95% confidence interval “CI": 0.24-0.83, p=0.010). Compared to patients treated with oral hypoglycemic only, those treated with insulin only or both oral hypoglycemic and insulin were at increased risk for DR (AOR=4.68; 95%CI: 1.89-11.53, p=0.001 and AOR=3.71; 95%CI: 2.09-6.59, p<0.001, respectively). Those with hypertension were at higher risk for DR compared to those without it (AOR=1.69; 95%CI: 1.01-2.92, p=0.049). Patients with other chronic diseases were at higher risk for DR than others (AOR=1.93; 95%CI: 1.04-3.59, p=0.038). Considering patients without diabetic neuropathy or nephropathy as reference categories, those with diabetic neuropathy or nephropathy were at almost double risk of developing DR (AOR=1.85; 95%CI: 1.15-2.97, p=0.010 and AOR=1.78; 95%CI: 1.04-3.04, p=0.035, respectively). Increase in the levels of creatinine or HbA1c% by one unit was significantly associated with increase in the risk of DR (AOR=1.13; 95%CI: 1.01-1.28, p=0.047 and AOR=1.15; 95%CI: 1.01-1.33, p=0.049, respectively). High serum uric was not significantly associated with DR, after controlling for confounding effect. Conclusion: Diabetic retinopathy is prevalent among type 2 diabetic patients attending the University Diabetes Center, King Abdul-Aziz University Hospital, Riyadh, Saudi Arabia with some identified determinants; however, association with serum uric acid is not conclusive.