Metabolic profiles and malnutrition in hospitalized adults: A metabolomic cohort study

Malnutrition or risk of malnutrition is present in about one-third of patients admitted to Western hospitals and is identified by either screening for malnutrition or further nutrition assessment. To date, there are no commonly accepted biomarkers of malnutrition, which could expedite screening efforts, ease diagnosis, and hasten treatment. We aimed to investigate whether metabolomics could identify markers associated with malnutrition in hospitalized patients and performed a retrospective metabolomic cohort study in this patients' group. The study population included adult patients hospitalized in a medical unit. Malnutrition was identified by the second step of the Global Leadership Initiative on Malnutrition criteria independently of the outcome of the screening step (nutritional risk screening 2002). Amino acids were determined by targeted metabolomics using gas chromatography-tandem mass spectrometry and liquid chromatography-tandem mass spectrometry. Logistic regression analyses with Benjamini-Hochberg procedure to reduce false discovery rate were used to identify biomarkers associated with malnutrition. In total, 218 patients were included in the final analysis, with 62 patients having a diagnosis of malnutrition. In crude analyses, 11 metabolites were associated with malnutrition, but further adjustment attenuated the associations. After multiple adjustment, neopterin and cystatin C were positively associated with malnutrition, whereas His, Cys, and kynurenine to tryptophan ratio were negatively associated. The observed associations require confirmation in a replication cohort before they can be recommended as biomarkers of malnutrition.