Association between serum homocysteine levels and diabetic macular edema in type 2 diabetes mellitus: A cross-sectional study in Western Uttar Pradesh

Abstract Objective: To investigate the association between serum homocysteine levels and diabetic Macular edema (DME) in individuals with type 2 diabetes mellitus (T2DM). Materials and Methods: A cross-sectional study was conducted on 120 T2DM patients aged ≥40 years, equally divided into DME and non-DEME groups. Central Macular thickness (CMT) was assessed using optical coherence tomography, and serum homocysteine levels were measured under fasting conditions. Associations with CMT, visual acuity, and HbA1c were analyzed. Statistical significance was set at P < 0.05. Results: Mean serum homocysteine levels were significantly higher in the DME group (16.74 μmol/L) than in the non-DME group (13.67 μmol/L; P < 0.001). Homocysteine levels correlated positively with CMT ( r = 0.62), visual acuity ( r = 0.58), and HbA1c ( r = 0.45). Regression analysis identified homocysteine as an independent predictor of DME severity ( β = 0.58). Receiver operating characteristic analysis demonstrated an area under the curve of 0.82 at a cutoff of ≥12.5 μmol/L. Conclusion: Elevated serum homocysteine levels are significantly associated with both the presence and severity of DME in patients with T2DM. Homocysteine may be considered a potential biomarker for early detection and risk stratification.