Branched chain amino acids, cardiometabolic risk factors and outcomes in older men: the Concord Health and Ageing in Men Project
D. Le Couteur, R Ribeiro, A. Senior, B. Hsu, V. Hirani, F. Blyth, L. Waite, S. Simpson, V. Naganathan, R. Cumming and D. Handelsman
Centre for Education and Research on Ageing, ANZAC Research Institute and Charles Perkins Centre, University of Sydney, Sydney, New South Wales, Australia
Increased blood levels of branched chain amino acids are associated with cardiometabolic risk factors. We studied community-dwelling older men to determine the relationship between BCAAs and other amino acids with cardiometabolic risk factors, major cardiovascular endpoints (MACE) and mortality. BCAAs were associated with many metabolic risk factors (glucose, insulin, HOMA-IR, triglycerides; HDL cholesterol). However, participants with low BCAAs had increased mortality and MACE because increasing age and frailty, both of which were associated with lower BCAA levels, are key risk factors for these outcomes. Overall, amino acids that were lowest in frail subjects (BCAAs, α-aminobutyric acid (AABA), histidine, lysine, methionine, threonine, tyrosine) were also associated with mortality and MACE. BCAAs are biomarkers for cardiometabolic risk factors, frailty and mortality in older men. In old age, frailty becomes the main risk factor for MACE and mortality.