High-resolution plasma metabolomics and thiamine status in critically ill adult patients

To determine the association between whole blood thiamine pyrophosphate (TPP) concentrations in critically ill patients and plasma metabolites and linked metabolic pathways using high resolution metabolomics. Patients and methods This cross-sectional study was performed at Erciyes University Hospital, Medical Intensive Care Unit (ICU), Kayseri, Turkiye and Emory University Department of Medicine Clinical Biomarkers Laboratory, Atlanta, GA, USA. Participants were enrolled as follows;≥18 years of age, with an expected length of ICU stay longer than 48 h and receiving furosemide therapy for at least 6 months or longer before ICU admission. Results Blood for TPP and metabolomics was obtained on the first day of ICU admission. Whole blood TPP concentrations were measured using high-performance liquid chromatography (HPLC). Liquid chromatography/mass spectrometry for high-resolution metabolomics was performed in plasma samples. Data was analyzed using regression analysis of TPP levels against all plasma metabolomic features (putative metabolites) in metabolome-wide association studies. We also compared metabolomic features from patients in the highest TPP concentration tertile to patients in the lowest TPP tertile as a secondary analysis. We enrolled 76 participants with a median age of 69 (range, 62.5–79.5) years. Specific pathways associated with whole blood TPP levels using both regression and tertile analysis included pentose phosphate, fructose and mannose, branched chain amino acid, arginine and proline, linoleate, and butanoate pathways. Conclusion Plasma high-resolution metabolomics analysis shows that TPP levels are significantly associated with metabolites and pathways linked to the metabolism of energy, amino acids, lipids and the gut microbiome in adult critically ill patients. These data suggest that monitoring of thiamine status and thiamine repletion to maintain adequate thiamine concentrations may facilitate metabolic homeostasis in adults requiring intensive care.