The impact of diabetes duration on left ventricular diastolic function and cardiovascular disease

OBJECTIVES: The question of whether diabetes mellitus (DM) duration correlates with the severity of dysfunction has not been well studied. We hypothesised that the longer the duration of DM the worse the severity of left ventricular (LV) diastolic dysfunction and increased risk of cardiovascular disease (CVD). METHODS: We reviewed 547 diabetic patients between January 2005 and April 2010. Finally, 92 consecutive patients who presented with type 2 DM and who underwent echocardiographic assessment were enrolled according to the selection criteria. In all patients, ischaemic heart disease and heart failure were excluded. RESULTS: Diastolic parameters were significantly worsened with increasing duration of DM (p<0.05). In the ≥7 years DM duration group (n=50), the E/Ea ratio increased significantly and the Ea/Aa ratio decreased significantly, compared with those in the <7 years DM duration group (n=42). CVD developed in 28 patients (30.4%) during the follow-up period. However, the duration of DM showed less statistical correlation with the incidence of CVD (p=0.188) and other LV diastolic function indices did not differ significantly between groups with or without CVD. CONCLUSIONS: Alteration of diastolic function induced by DM worsens with increasing duration of DM. DM duration on echocardiographic evaluation time did not differ significantly between the CVD incident and the non-CVD incident groups. The rate of CVD development was not significantly different if the duration of DM was more than 7 years. Therefore, active medical care including echocardiography should be undertaken to prevent CVD from the point of diagnosis of type 2 DM.