Cardiovascular disease in Chinese type 2 diabetic women is associated with a prolonged QTc interval

We studied the relationships between QT interval and cardiovascular disease status in 192 Chinese type 2 diabetic patients. Of these 192 subjects, 132 (68.8%) were women and 60 (31.2%) were men. The mean age (±S.D.) was 56.6±12.9 years (range: 23–84, median: 58.0 years). Women had longer QTc interval compared to men (0.402±0.030 s vs. 0.387±0.026 s, P<0.01). Of the 192 subjects, 18 women and two men had prolonged QTc interval (QTc >0.433 s). Women with prolonged QTc interval have a 2.8-fold greater rate of cardiovascular disease as compared to those with normal QTc interval (38.9% vs. 14.0%, P<0.05). Using multiple regression analysis (stepwise) to assess the relationship with QTc interval with age, sex, body mass index, waist–hip ratio, blood pressure, fasting plasma glucose, glycated haemoglobin, lipid profiles, smoking and duration of diabetes as independent variables (R2=0.146, F=8.88, P<0.001), systolic blood pressure (β=0.198, P=0.017), age (β=0.189, P=0.023) and female gender (β=0.157, P=0.037) were found to be independently associated with QTc interval. In conclusion, we have shown a significant association between prolonged QTc interval, ischaemic heart disease and cardiovascular disease in Chinese type 2 diabetic women. Age, systolic blood pressure and female gender are independently correlated to QTc interval.