Targeted Metabolomic Profiling of Plasma and Survival in Heart Failure Patients

OBJECTIVES This study sought to derive and validate plasma metabolite associations with survival in heart failure (HF) patients. BACKGROUND Profiling of plasma metabolites to predict the course of HF appears promising, but validation and incremental value of these profiles are less established. METHODS Patients (n = 1,032) who met Framingham HF criteria with a history of reduced ejection fraction were randomly divided into derivation and validation cohorts (n = 516 each). Amino acids, organic acids, and acylcarnitines were quantified using mass spectrometry in fasting plasma samples. We derived a prognostic metabolite profile (PMP) in the derivation cohort using Lasso-penalized Cox regression. Validity was assessed by 10-fold cross validation in the derivation cohort and by standard testing in the validation cohort. The PMP was analyzed as both a continuous variable (PMPscore) and dichotomized at the median (PMPcat), in univariate and multivariate models adjusted for clinical risk score and N-terminal pro-B-type natriuretic peptide. RESULTS Overall, 48% of patients were African American, 35% were women, and the average age was 69 years. After a median follow-up of 34 months, there were 256 deaths (127 and 129 in derivation and validation cohorts, respectively). Optimized modeling defined the 13 metabolite PMPs, which was cross validated as both the PMPscore (hazard ratio [ HR]: 3.27; p < 2 x 10(-16)) and PMPcat (HR: 3.04; p = 2.93 x 10(-8)). The validation cohort showed similar results (PMPscore HR: 3.9; p < 2 x 10(-16) and PMPcat HR: 3.99; p = 3.47 x 10(-9)). In adjusted models, PMP remained associated with mortality in the cross-validated derivation cohort (PMPscore HR: 1.63; p = 0.0029; PMPcat HR: 1.47; p = 0.081) and the validation cohort (PMPscore HR: 1.54; p = 0.037; PMPcat HR: 1.69; p = 0.043). CONCLUSIONS Plasma metabolite profiles varied across HF subgroups and were associated with survival incremental to conventional predictors. Additional investigation is warranted to define mechanisms and clinical applications. (C) 2017 by the American College of Cardiology Foundation.