Identifying Risk Factors for Clinically Significant Diabetic Macula Edema in Patients with Type 2 Diabetes Mellitus

High clinic blood pressure (BP), male sex, cigarette smoking, dyslipidemia, renal function, anemia and thiazolidenediones (TZD) treatment are known predictors for clinically significant diabetic macula edema (CSDME). This study was performed to identify the most significant risk factors for CSDME in Japanese patients with type 2 diabetes mellitus (T2DM) and retinopathy (DR), using optical coherence tomography (OCT) if necessary, by multiple regression analysis. One of the risk factors was BP in awakening. Seven diabetic Japanese patients with CSDME (group 1) and 124 subjects without CSDME (group 2) with DR on OCT were studied. The durations of T2DM in groups 1 and 2 were 15 ± 10 years and 20 ± 15 years, respectively. There was no significant difference in sex distribution, duration, age, body mass index (BMI), and HbA1c, lipids (TC, LDL, TC/HDL), creatinine and Hb levels, urinary albumin excretion rate, cigarette smoking, and clinic BP between two groups. Morning systolic home BP (MSHBP) and foveal thickness were significantly (p<0.001) greater in group 1 than in group 2, and visual acuity was significantly (p<0.001) lower in group 1 than group 2. The patients in both groups had received various kinds of drugs for hyperglycemia, hypertension and others. There were no significant differences in the prevalence of other variables between two groups. On multiple regression analysis, MSHBP and nephropathy were significantly (p <0.03) positive predictors for CSDME, while BMI had a significantly (p <0.001) negative predictor. Other variables were not significantly correlated to CSDME. Thus, MSHBP is a predictive factor for CSDME that can be added to the previously reported risk factors in patient with T2DM.