ESPEN 2020 Abstract Submission

Topic: Protein and amino acid metabolism

Abstract Submission Identifier: ESPEN20-ABS-1598

BETA-HYDROXY-BETA-METHYLBUTYRATE (HMB) MODIFIES AMINO ACID METABOLISM IN CRITICALLY ILL PATIENTS. A RCT

M. V. Viana ¹, F. Becce ², S. Schmidt ², G. Bagnoud ¹, M. M. Berger^*, ¹, N. E. Deutz ³

¹Adult intensive care, ²Radiology, CHUV, Lausanne, Switzerland, ³Dpt of Health & Kinesiology, Texas A&M University, College Station, United States

Rationale: The etiology of the alterations in metabolism observed during critical illness is multi-factorial, being associated with for instance inflammation that favors catabolism, or immobilization or insufficient nutritional coverage of energy and protein needs. The study aimed at testing if HMB, a metabolite of leucine, could modify amino acid metabolism in the critically ill (ICU) patient

Methods: RCT in 37 critically ill patients (ITT), on mechanical ventilation, with full treatment and a functional gastro-intestinal tract. Intervention:  Enteral HMB 2*1.5 g/day versus placebo from day 4 to day 15 after admission. Nutrition as per ICU protocol guided by indirect calorimetry. On days 4 and 15, amino acid metabolism was investigated with the pulse administration of a mixture of stable amino acid tracers (1). Plasma enrichments and metabolite concentrations were measured by LC-MS/MS, and areas under the curve (AUC) were calculated to determine whole body production and interconversions of several amino acids (1).

Results: Critically ill patients with age 65±15 years and SAPS 47 ±12 were studied. Energy (1390 kcal/day) and protein intakes (0.84 g/kg/day) did not differ between groups.  Seven patients had amino acids kinetic evaluated only at day 4, 30 completing the trial. There was no significant difference in production of essential amino acids and branched chain amino acids over time (p=0.1148 and p=0.1758, respectively) and also no interaction between groups (p =0.2163 and p=0.2144, respectively.) However, the HMB group had a significant higher conversions over time of arginine to citrulline (nitric oxide synthesis: p=0.0093) and glutamate to glutamine (p=0.038). In addition, the HMB group showed over time a higher citrulline production (0.0026).

Conclusion: HMB had no effect in essential and branched chain amino acids production, indicating no effect of HMB on protein kinetics. In contrast, HMB induced specific changes in amino acid metabolism that need to be further explored.

References: 1. Deutz NE, et al. Metabolic phenotyping using kinetic measurements in young and older healthy adults. Metabolism: 2018;78:167-78.

The study was funded by 1) ESPEN fellowship, 2) excellence fellowship of the Swiss Dpt of foreign affairs (DFAE)

Disclosure of Interest: None Declared

Keywords: muscle protein synthesis