Correlation Between Diabetic Retinopathy Severity and HbA1c Levels

Abstract

Background: Diabetic retinopathy is a leading microvascular complication of diabetes, and hyperglycemia over a long period of time is an important modifiable risk factor for its onset and progression. The study aimed to assess the association of HbA1c with the severity of DR.

Material and Methods: A cross-sectional analytical study was carried out with 77 diabetes mellitus (DM) adult patients attending medical outpatient department of Mardan Medical Complex, Mardan from December 2022 to May 2023. All participants had standardized ophthalmic examination and HbA1c testing. Diabetic retinopathy was classified as none or proliferative diabetic disease. The correlation between HbA1C and severity of retinopathy was evaluated using Spearman's correlation.

Results: The mean age was 58.7 ± 9.8 years, and 55.8% were male. Diabetic retinopathy was present in 47 (61.0%) participants. The mean HbA1c was significantly higher in participants with PR (11.1 ± 0.9%) than those without retinopathy (6.9 ± 0.8%). HbA1c showed a strong positive correlation with the severity of retinopathy (ρ=0.69, p<0.001). There was also a moderate positive correlation between Diabetes duration and severity (ρ=0.46, p<0.001). The prevalence of diabetic macular edema, vitreous hemorrhage, and retinal neovascularization was all significantly associated with higher HbA1c.

Conclusion: There was a strong association between increasing HbA1c concentrations and increasing severity of diabetic retinopathy and advanced ophthalmic complications.

Keywords: Diabetic retinopathy; HbA1c; Glycemic control; Retinopathy severity; Diabetes mellitus