Low initial body fat percentage exacerbates skeletal muscle loss and increases the risk of hyperuricemia during high-altitude acclimatization in young men

Background The incidence of hyperuricemia (HUA) increases significantly after individuals ascend to a high-altitude environment, particularly among young men. Previous studies have shown correlations between skeletal muscle mass, fat mass, and serum uric acid levels. However, whether changes in body composition under high-altitude conditions influence the occurrence of HUA has not been reported. Objectives This study aimed to investigate the effects of initial body fat percentage (BF%) and changes in body composition on the development of HUA in young men after 1 year at high altitude. Methods In this prospective observational study, 216 young men who relocated from a plain area to a high-altitude area for 1 year were enrolled. Data on basic information, body composition, and laboratory measurements were collected both before relocation and after the one-year period. Results After 1 year at high altitude, skeletal muscle mass (SMM) decreased significantly. Linear regression analysis revealed that the change in SMM was correlated with the initial BF%; a lower initial BF% was associated with a more pronounced decrease in SMM ( b = 0.186, p < 0.001). A total of 136 participants (62.96%) were diagnosed with HUA after 1 year. Binary logistic regression analysis revealed high altitude (OR = 2.217, p < 0.05), low SMM (OR = 0.920, p < 0.05), low initial BF% (4–8%: OR = 3.142, p < 0.05; ≤4%: OR = 4.489, p < 0.01), and a decrease in SMM (−1.5 to −2.5 kg: OR = 2.599, p < 0.05; ≤−2.5 kg: OR = 3.263, p < 0.05) as risk factors for HUA. After adjusting for altitude and SMM, a decrease in SMM (−1.5 to −2.5 kg: OR = 2.735, p < 0.05; ≤−2.5 kg: OR = 3.198, p < 0.05) and low initial BF% (4–8%: OR = 2.687, p < 0.05;