Effects of SGLT2 Inhibitors on Cardiac Mechanics in Hispanic and Black Diabetic Patients

Abstract

Background: Clinical trials demonstrating improved cardiovascular outcomes with SGLT2 inhibitors have often had limited representation from Black and Hispanic populations. While the mechanisms of action are not well known, ethnicity- or gender-based receptor physiology may render SGLT2 inhibitors a better agent in certain populations over others. Methods: A medical records query yielded diabetic patients initiated on SGLT2 inhibitors between 2013 and 2020. Patients with coronary artery disease, cardiac arrhythmias, and heart failure were excluded. Transthoracic echocardiographic studies (TTE) before and after starting SGLT2 inhibitors were analyzed, and post-processing left ventricular global longitudinal strain (LV GLS) analysis was also performed on each echocardiographic study. Univariate outliers and patients with missing data were excluded. Results: Among 94 patients with TTE (mean age 60.7 years; 68% Hispanics, 22.3% Blacks; median follow up of 7 months), there were significant improvements in the mean LV GLS (−15.3 vs. −16.5; p = 0.01), LV mass (LVM) (198.4 ± 59.6 g vs. 187.05 ± 50.6 g; p = 0.04), and LV mass index (LVMI) (100.6 ± 26.6 g/m2 vs. 94.3 ± 25.4 g/m2; p = 0.03) before and after initiating SGLT2 inhibitors but no significant change in the ratio (MV E/E’) of peak early diastolic mitral flow velocity (E) and spectral pulsed-wave Doppler-derived early diastolic velocity from the septal mitral annulus (E’) (12.5 ± 5.7 vs. 12.7 ± 4.8; p = 0.38). Changes in HbA1c (r2 = 0.82; p = 0.026), LVM (r2 = 0.20; p = 0.04), and LVMI (r2 = 0.20; p = 0.04) were found to be independently associated with changes in values of LV GLS on follow-up echocardiograms, when compared to the pre-medication LV GLS number. Conclusion: Non-White diabetic patients receiving SGLT2 inhibitors against a backdrop of other cardioprotective medications demonstrate significant improvements in LV remodeling and LV GLS, driven in part by an improvement in glycemic control. Large, prospective studies are needed to explore the differences in the therapeutic actions of SGLT2 inhibitors among different populations.