Association Between Diabetes Mellitus and Left Atrial Strain in Individuals With Hypertension

PURPOSE: Atrial remodeling is frequent in patients with diabetes and hypertension, linked to cardiovascular events and elevated left ventricular (LV) filling pressures. Speckle-tracking echocardiography detects these changes early, but data on left atrial (LA) strain in this specific population remain limited and controversial. METHODS: Individuals with primary hypertension were divided into two groups: with diabetes DM(+) and without diabetes DM(-). All subjects underwent transthoracic echocardiography. Clinical and echocardiographic characteristics, including LA reservoir (S-LAr), LA conduit (S-LAc), and LA contractile (S-LAct) strains, were compared between the groups. The association between diabetes and LA strain was evaluated in models adjusted for sex, age, body mass index (BMI), ambulatory systolic blood pressure, and LV mass index (LVMI). A possible role of diastolic dysfunction and LV strain on the association between DM and LA strain was evaluated by mediation analyses. RESULTS: A total of 64 patients were included: 29 (45.3%) had both diabetes and hypertension, while 35 (54.7%) had isolated hypertension. Standard echocardiographic parameters did not differ significantly between the DM(+) and DM(-) groups. S-LAr and S-LAc were lower in DM(+) compared to DM(-) (S-LAr: 27.8% ± 7.0% vs. 32.1% ± 6.4%, respectively, p = 0.013; S-LAc: 12.0% ± 4.8% vs. 16.0% ± 5.1%, respectively, p = 0.002). S-LAct was not significantly different between DM(+) and DM(-). After adjusting for multiple variables, diabetes remained significantly associated with lower S-LAr and S-LAc. In mediation analyses, the effect of DM on S-LAr and S-LAc was almost entirely attributed to a direct effect and not mediated by diastolic dysfunction or LV strain. CONCLUSION: Diabetes was associated with reduced S-LAr and S-LAc in individuals with hypertension. Speckle-tracking echocardiography may be a more sensitive tool for detecting early atrial dysfunction in this population.