A Cross-Sectional Study of the Association of Serum Uric Acid Levels and Sarcopenia using the China Health and Retirement Longitudinal Study (CHARLS)

Previous research has yielded inconsistent findings concerning the relationship between serum uric acid (UA) levels and sarcopenia. However, there is currently no research that comprehensively examines this relationship within the broader Chinese population. This study aims to explore the relationship between serum uric acid levels and sarcopenia in Chinese adults aged 45 and above, focusing specifically on age-related variations. The present study involved 10,938 participants of the 2015 China Health and Retirement Longitudinal Study (CHARLS). The associations between sarcopenia (including its components) and serum uric acid levels were evaluated using weighted logistic and weighted linear regression models. After categorizing participants by age groups, the subgroup analysis conducted allowed for a more detailed examination of age-related changes. Participants were stratified into quartiles based on their uric acid levels. Adjusted analyses revealed that a higher serum uric acid level was negatively associated with sarcopenia only in individuals aged 65 and older. Results from weighted linear regression analysis indicated a statistically significant positive correlation between serum uric acid levels and both handgrip strength (HGS) and skeletal muscle index (SMI). Moreover, the Q4 group (≥5.70 mg/dL) sustained this positive correlation across all ages. The results showed that higher UA levels were significantly associated with increased SMI and HGS in Chinese people aged 45 years and older. Elevated levels of blood uric acid may potentially exert a safeguarding influence against the onset of sarcopenia, particularly in individuals aged 65 years and above.