To demonstrate the change in macular thickness using optical coherence tomography in diabetic patients and to assess its relationship with glycosylated hemoglobin (HbA1c) levels and hypertension state.


Diabetic patients who underwent at least two macular thickness measurements with OCT within a 12-month period were include d. HbA1c values within 1 month of each OCT study, and clinical data such as age, insulin treatment, systemic hypertension, and the severity of diabetic retinopathy were collected. The change in three macula parameters including center point thickness (CPT), central subfoveal macular thickness (CSMT), and total macular volume (TMV) between two measurements was calculated. Patients were divided into two groups based on the half-width of the 95% confidence interval for percent change, the increase group (group 1) and the decrease group (group 2). The associations of CPT change, CSMT change, and TMV change with baseline HbA1c levels, HbA1c change, and degree of hypertension were investigated using correlation analysis and group comparison.

Effectiveness / Safety:

A total of 68 eyes of 32 patients were studied. In correlation analysis; the increase in CPT, CSMT, and TMV was correlated with baseline HbA1c (CPT, Spearman’s rho = 0.482, p = 0.020; CSMT, Spearman’s rho = 0.472, p = 0.025; TMV, Spearman’s rho = 0.520, p = 0.014), and the change of HbA1c (CPT, Spearman’s rho = -0.566, p = 0.01; CSMT, Spearman’s rho = -0.582, p = 0.004; TMV, Spearman’s rho = -0.720, p < 0.001). The increase in CPT, CSMT, and TMV was correlated with baseline systolic blood pressure (CSMT, Spearman’s rho = 0.452, p = 0.035; TMV, Spearman’s rho = 0.479, p = 0.019). The change in macular thickness and volume developed in relation to HbA1c levels during a less than 12-month period. A high baseline HbA1c, a large reduction of HbA1c, and baseline systolic blood pressure were risk factors for the increase in macular thickness.