We sought to determine the predictors of primary episodes of mild diastolic dysfunction (DD) in a cohort of women aged 445 years, who had >2 echocardiography from 2009 to 2012. Patients were excluded if they had prior diagnosis of coronary artery disease, heart failure, valvular heart disease or echocardiographic evidence of DD. Mild DD was defined as: left ventricular ejection fraction >50%, E/A ratio <0.75, and E/e' <= 8. Out of the total 758 subjects (age 64.15 +/- 7.24 years), 109 (14.3%) had developed mild DD, during a mean followup period of 3 years. Independent predictors of mild DD included: age (P < 0.001), history of hypertension (P = 0.022), body mass index (BMI) (P < 0.001), total triglycerides (TG) (P = 0.016), inter ventricular septal thickness (P = 0.015) and brachial-ankle pulse wave velocity (baPWV)>= 16 ms(-1) (P < 0.001). E/A ratio was inversely associated with age (r = -0.337, P < 0.001), baPWV (r=-0.359, P < 0.001), BMI (r=-0.290, P < 0.001) and TG (r =-0.255, P < 0.001). The Area Under roc Curve for a linear combination of age, BMI, baPWV and TG was 0.738 (95% confidence interval: 0.683-0.804, P < 0.001), which was superior to any of the variables taken alone. In summary, many middle-aged or elderly women may develop mild DD within a relatively short period of 3 years. Several subclinical abnormalities and cardiovascular parameters were determined to contribute to the onset of DD.