Abstract
BACKGROUND: Metabolic dysfunction is a hallmark of differential aging, specifically in African Americans. Investigation of systemic metabolic state, multiorgan aging, and long-term cardiovascular outcome in African Americans has not been reported. METHODS: We studied 291 African American males in the Health, Aging, and Body Composition (Health ABC) study to identify circulating metabolites related to the Newman healthy aging index (HAI; a multiparametric score comprised of blood pressure, blood glucose, neurocognitive function, creatinine, and forced vital capacity). We examined the relationship of selected metabolites differential abundant at the extremes of HAI with long-term survival from cardiovascular mortality. RESULTS: The median age was 73 years. We identified 19 metabolites differentially expressed in blood in 86 study participants at the extremes of HAI (HAI 0-3: N = 30 vs 8-10: N = 56). At a median follow-up of 10 years, 78 participants (27 per cent) died from cardiovascular causes. After adjustment for age, body mass index, presence of prevalent cardiovascular disease, creatinine, and HAI, six of these 19 metabolites were associated with long-term cardiovascular mortality. Although several metabolites had been previously reported in Caucasians (eg, isocitrate), we identified several metabolites with unreported association with cardiac disease. Metabolites associated with HAI and cardiac death in African Americans specified pathways relevant to nitric oxide, oxidative stress, mitochondrial function, urea cycle, and gut microbial metabolism. CONCLUSIONS: Metabolite profiling in African Americans identified known and novel metabolic pathways linked to HAI and cardiovascular death. Further investigation in larger patient cohorts is required to uncover race-based signatures of cardiovascular disease with aging.