Biomarkers of left ventricular hypertrophy and remodeling in blacks

Abstract

Left ventricular (LV) hypertrophy, a marker for adverse cardiovascular events, is more common in blacks than in non-Hispanic whites. Mechanisms leading to LV hypertrophy and mediating its clinical sequelae in blacks are not fully understood. We investigated the associations of 39 candidate biomarkers in distinct biological pathways with LV mass and geometry in blacks. Participants included 1193 blacks (63±9 years of age; 72% women; 78% hypertensive) belonging to hypertensive sibships. LV mass was measured by transthoracic echocardiography and indexed to height.(2.7) LV geometry was categorized as normal, concentric remodeling, concentric hypertrophy, and eccentric hypertrophy. Generalized estimating equations were used to assess associations of the 39 biomarkers with LV mass index after adjustment for age, sex, and conventional risk factors. After adjustment for potential confounders, log-transformed levels of the following biomarkers were independently associated with LV mass index: N-terminal pro-brain natriuretic peptide (β±SE=0.07±0.01 pg/mL; P<0.0001), mid-regional pro-atrial natriuretic peptide (β±SE=0.08±0.02 pmol/L; P<0.0001), mid-regional pro-adrenomedullin (β±SE=0.09±0.03 nmol/L; P=0.0006), C-terminal pro-endothelin (β± SE=0.05±0.02 pmol/L; P=0.0009), and osteoprotegerin (β±SE=0.07±0.02 pg/mL; P=0.0005) (β is for 1 log increase in biomarker level). The associations of these biomarkers with LV mass index were mainly due to their association with eccentric hypertrophy. Higher circulating levels of natriuretic peptides, adrenomedullin, endothelin, and osteoprotegerin were associated with increased LV mass index, providing insights into the pathophysiology of LV hypertrophy in blacks.