Metabolic profiles in adults with trauma receiving enteral nutrition support: A metabolomic cohort study

BACKGROUND: We aimed to identify metabolic changes after injury and potential mechanisms whereby nutrition support may influence metabolites and pathways. We analyzed 45 metabolites in 67 trauma patients. METHODS: We performed a metabolomic cohort study in critically ill adults with trauma using nuclear magnetic resonance to quantify 45 metabolites in plasma. We divided the cohort into two groups based on the median amount of protein intake calculated by averaging over the first 7 days of nutrition support. Using linear mixed models, we tested the hypotheses that metabolite concentrations would differ over time and the rate of change is altered by the amount of enteral protein intake. RESULTS: Five metabolites in each of the low (median = 0.6 [IQR, 0.4-0.8] gm/kg/day) and high (1.5 [1.1-1.7] gm/kg/day) protein intake groups were different by day 3 compared with baseline. Twenty metabolites in the low-protein intake group and 14 metabolites in the high-protein intake group were different by day 7 compared with baseline. There was no evidence that the rate of metabolite change over time differs by protein intake group. Quantitative enrichment analysis indicated that branched chain amino acid (BCAA) catabolism was one of the most altered pathways in both groups. CONCLUSION: In critically ill trauma patients, metabolites, particularly those linked with BCAA metabolism, are altered over time but not influenced by the amount of enteral protein intake during the first week.