Differences in Diastolic Function and Global Longitudinal Strain on Stress Echocardiography Between Elderly Diabetic and Non-Diabetic Patients

pp. 183-188

Abstract

Background: Diabetes mellitus (DM) is a disease with increasing prevalence due to population aging. According to the Framingham study, DM is associated with an increased risk of heart failure in both women and men, regardless of the presence of concomitant coronary artery disease. In its early stages, diabetic cardiomyopathy is characterized by an almost always preserved left ventricular ejection fraction (LVEF), with reduced global longitudinal strain (GLS) and diastolic dysfunction.

Objective: The following study was conducted to describe alterations in diastolic function and GLS and their associations in a population of elderly diabetic patients.

Methods: This was an observational cohort study including consecutive patients undergoing a stress echocardiogram in our department, excluding those diagnosed with coronary artery disease. Diastolic function variables (E velocity, e’ velocity and E/e’ ratio) were measured, and patients were categorized as presenting normal diastolic function or mild (Grade 1), moderate (Grade 2), or severe (Grade 3) diastolic dysfunction. Speckle tracking was used to measure global longitudinal strain. 6 years Diabetic patients were compared with non-diabetic patients. Multivariate analysis was performed to identify the predictors of significant diastolic dysfunction (moderate or severe) and GLS. A p-value <0.05 was considered statistically significant.

Results: The study included 176 diabetic patients and 771 non-diabetic ones, with a mean age of 73 ± 6 years. Diabetic patients exhibited greater diastolic function parameter abnormalities  at rest and during exercise compared with non-diabetic patients, as well as a significant reduction in GLS. The group with DM had a higher percentage of significant diastolic dysfunction both at rest (12.5% vs. 7.5%, p<0.001) and during exercise (35% vs. 23%, p<0.001). Left ventricular ejection fraction was normal and similar in both groups (p=0.417). Global longitudinal strain was lower in patients with DM (-15.20% vs. -16.21% in patients without DM; p<0.001). In logistic regression analysis, DM was an independent predictor of significant diastolic dysfunction and an independent predictor of GLS. Only one patient in the diabetic group presented with LVEF <50%. 

Conclusion: In this population of elderly patients without ischemic heart disease, DM was independently associated with a higher prevalence of diastolic dysfunction, both at rest and during exercise, and with a reduction in stroke volume despite preserved left ventricular ejection fraction. These findings are consistent with the concept of a predominantly subclinical diastolic diabetic cardiomyopathy.