Race-ethnic differences in subclinical left ventricular systolic dysfunction by global longitudinal strain: A community-based cohort study

Race-ethnic differences exist in the epidemiology of heart failure, with blacks experiencing higher incidence and worse prognosis. Left ventricular (LV) systolic dysfunction (LVSD) detected by speckle-tracking global longitudinal strain (GLS) is a predictor of cardiovascular events including heart failure. It is not known whether race-ethnic differences in GLS-LVSD exist in subjects without overt LV dysfunction. Methods: Participants from a triethnic community-based study underwent 2-dimensional echocardiography with assessment of LV ejection fraction (LVEF) and GLS by speckle-tracking. Participants with LVEF <50% were excluded. Left ventricular systolic dysfunction by GLS was defined as GLS >95% percentile in a healthy sample (-14.7%). Results: Of the 678 study participants (mean age 71 ± 9 years, 61% women), 114 were blacks; 464, Hispanics; and 100, whites. Global longitudinal strain was significantly lower in blacks (-16.5% ± 3.5%) than in whites (-17.5% ± 3.0%) and Hispanics (-17.3% ± 2.9%) in both univariate (P = .015) and multivariate analyses (P = .011), whereas LVEF was not significantly different between the 3 groups (64.3% ± 4.6%, 63.4% ± 4.9%, 64.7% ± 4.9%, respectively, univariate P = .064, multivariate P = .291). Left ventricular systolic dysfunction by GLS was more frequent in blacks (27.2%) than in whites (19.0%) and Hispanics (14.9%, P = .008). In multivariate analysis adjusted for confounders and cardiovascular risk factors, blacks were significantly more likely to have GLS-LVSD (adjusted odds ratio 2.6, 95% CIs 1.4-4.7, P = .002) compared to the other groups. Conclusions: Among participants from a triethnic community cohort, black race was associated with greater degree of subclinical LVSD by GLS than other race-ethnic groups. This difference was independent of confounders and cardiovascular risk factors.