Predictors of Diabetic Retinopathy in Patients with Type 2 Diabetes Who Have Normoalbuminuria
Background: Microalbuminuria is an independent predictor of retinopathy, so absence of microalbuminuria may tend clinician not to screen for diabetic retinopathy (DR).
Aim: The aim of our study was to estimate prevalence of DR in patients with type 2 diabetes who have normoalbuminuria, and to study predictors for DR, which can identify these high‑risk individuals.
Subjects and Methods: In a prospective cross‑sectional study that included patients with type 2 DM and normoalbuminuria. Diagnosis of DR was made by a trained ophthalmologist based on the presence of clinical features in the fundus of both eyes following the International Clinical DR guidelines. The statistical analyses were performed using Statistical Package for the Social Sciences 15.0 version software (Chicago, IL, USA).The continuous variables expressed as means (SD and Student’s t-test or Mann–Whitney test were used, as appropriate, to determine differences in them. Categorical variables were presented as percentage. The Pearson’s Chisquare test or Fisher’s exact test, as appropriate, was used to determine the differences in them.
Results: A total of 226 patients with type 2 DM and normoalbuminuria were enrolled in the study that included 110 males (48.6%), and 116 females (51.4%) Mean (SD) duration of diabetes was 8.2 (5.6) years. DR of any grade was present in 49/226 (22%) patients. Of the patients with DR of any grade, 31/49 (63%) had mild non‑proliferative diabetic retinopathy (NPDR) 10/49 (22%) had moderate to severe NPDR and 8/49 (15%) had PDR. Duration of diabetes (OR 1.01, 95% CI, 0.86‑2.2, P = 0.04), higher systolic blood pressure (OR 2.2, 95% CI, 1.6‑4.5, P = 0.01), low hemoglobin (OR 1.4, 95% CI, 0.45‑2.9, P = 0.01), and a higher tertile of urinary albumin excretion rate (OR 4.12, 95% CI, 1.92‑7.57, P = 0.001) had independently significant association with DR.
Conclusion: The risk of DR exists in patients with type 2 diabetes even in normoalbuminuric individuals. Close monitoring is particularly needed if patients have longer duration of diabetes, hypertension, anemia, or high normal albuminuria.
Keywords: Albuminuria, Diabetic retinopathy, Predictors, Type 2 diabetes mellitus