Influence of glycaemic control on macular thickness in diabetic retinopathy

Diabetic macular oedema (DME) is one of the major cause of decreased visual acuity in patients with diabetic retinopathy. Poor glycaemic control is associated with increased incidence of DME.

A total of 112 eyes of 112 patients were studied in this cross-sectional study and were classified into three groups based on HbA1c: group 1 included patients with good glycaemic control (HbA1c ≤7%), group 2 included patients with moderate glycaemic control (HbA1c between 7% and 9%) and group 3 included patients with poor glycaemic control (HbA1c ≥9%).

We included 112 eyes of 112 patients. The mean duration of diabetes mellitus (DM) was 11.37 years. In statistical analysis, CMT (mean 188.80 ± 27.64 μm) positively correlated with mean HbA1c level (7.95 ± 1.29%) (r = 0.238, p < .05). There was a significant difference in CMT values among the three groups of HbA1c (F (2,109) = 19.39, p < .001). Post hoc analysis showed statistical significance between HbA1c≤7% and HbA1c ≥9% group and HbA1c 7%-9% and ≥9% group. However, statistical significance was not found among HbA1c ≤7% group and HbA1c 7%-9% group. Multiple regression analyses showed a significant correlation between CMT and HbA1c after adjusting for age and duration of diabetes.

Serum HbA1c level has a significant correlation with CMT in diabetic patients.