Malignant LV hypertrophy may help explain elevated HF incidence in black population
Malignant left ventricular hypertrophy, a subtype in which patients have elevations in cardiac biomarkers associated with risk for HF, is more common in black individuals compared with white individuals and may partly help explain racial disparities in HF, researchers reported.
“Our study helps explain why African American men and women have disproportionately high rates of heart failure, a significant health disparity that persists despite considerable advances in cardiovascular care,” Alana Lewis, MD, a cardiology fellow at UT Southwestern Medical Center, said in a press release. “We hope these findings can help cardiologists identify those at higher risk for developing heart failure and intervene earlier.”
Lewis and colleagues analyzed 15,710 participants from three cohort studies — ARIC, MESA and the Dallas Heart Study — to determine whether prevalence of malignant LV hypertrophy was linked to racial disparities in incident HF.
All participants underwent an ECG and were stratified into three groups: those without LV hypertrophy (n = 14,289; mean age, 57 years; 43% men; 29% black), those with LV hypertrophy but normal high-sensitivity cardiac troponin T and N-terminal pro-B-type natriuretic peptide (n = 664; mean age, 54 years; 49% men; 65% black) or those with malignant LV hypertrophy, defined as LV hypertrophy and abnormal levels of either biomarker (n = 757; mean age, 61 years; 59% men; 58% black).
During 10 years of follow-up, HF occurred in 3.3% of the overall cohort, including in 5.2% of black men, 3.8% of white men, 3.2% of black women and 2.2% of white women, according to the researchers.
Malignant LV hypertrophy occurred three times more often in black participants than in white participants, Lewis and colleagues found.
Compared with participants with no LV hypertrophy, those with malignant LV hypertrophy had elevated risk for incident HF (adjusted HR = 2.8; 95% CI, 2.1-3.5), but those with LV hypertrophy and normal biomarkers did not (aHR = 0.9; 95% CI, 0.6-1.5), the researchers wrote, noting the trend was consistent for all subgroups according to race and sex.
When Lewis and colleagues conducted mediation analyses, they determined 33% of the excess HF hazard in black men and 11% of the excess HF hazard in black women was explained by the higher prevalence of malignant LV hypertrophy in black individuals.
Among black men, 30.8% who developed HF had malignant LV hypertrophy at baseline, for a population attributable fraction of 0.21 (95% CI, 0.11-0.3), according to the researchers.
The population attributable fraction was identical in white men (0.16; 95% CI, 0.1-0.22) and black women (0.16; 95% CI, 0.07-0.24) and was lowest in white women (0.09; 95% CI, 0.03-0.14), Lewis and colleagues wrote.
“Malignant LV hypertrophy is easily identifiable with widely used tests in the clinic, so now that we’ve found this association, we are hoping to identify patients with higher risk for heart failure earlier, when preventive interventions can have a greater impact on future risk,” James de Lemos, MD, professor of internal medicine at UT Southwestern Medical Center, said in the release. – by Erik Swain
Disclosures: Lewis reports no relevant financial disclosures. De Lemos reports he received grant support from Abbott Diagnostics and Roche Diagnostics, received consultant fees from Abbott Diagnostics, Amgen, Esperion, Novo Nordisk, Ortho Clinical Diagnostics, Quidel Cardiovascular, Regeneron and Roche Diagnostics, and along with two other authors has a patent pending for methods for assessing differential risk for developing HF. Please see the study for all other authors’ relevant financial disclosures.