Serum branched‐chain amino acid levels are associated with fracture risk in Japanese women

Aim Branched‐chain amino acids (BCAAs) have been shown to exert beneficial effects on muscle and bone metabolism; however, no studies to date have investigated whether BCAAs have beneficial effects on bone fractures. Herein, we aim to prospectively investigate the relationship between serum BCAA concentrations and the occurrence of vertebral fractures (VFs) in Japanese women. Methods During the observation period (7.5 ± 6.1 years), 188 of 983 participants experienced VF. Kaplan–Meier analyses were conducted to examine time‐dependent variations in the vertebral compression fracture occurrence rate. Patients were stratified into quartiles based on serum BCAA concentration for this analysis. Results The analysis results indicated that the group with the lowest BCAA level developed VFs significantly earlier and with a higher frequency than the other groups ( P < 0.001). A Cox proportional hazards model showed that BCAA concentration was a significant risk factor for incident fracture, even after adjusting for possible confounding factors. A series of multiple regression analyses were performed to identify factors related to serum BCAA concentration, with the results identifying levels of glycated hemoglobin ( P < 0.001), adiponectin ( P < 0.001), and NOx ( P = 0.011) as significant factors associated with serum BCAA. Conclusions Overall, the present study revealed that a lower serum BCAA level was an independent risk factor for incident VF in postmenopausal women. Geriatr Gerontol Int 2024; 24: 603–608 .