A cross-sectional study of the association of serum uric acid levels and sarcopenia in Chinese adults using the China Health and Retirement Longitudinal Study

Purpose Previous research has yielded inconsistent findings concerning the relationship between serum uric acid 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. Methods 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. Results Participants were stratified into quartiles based on their UA 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. Conclusion The results indicated a noteworthy correlation between higher UA levels and elevated skeletal muscle index (SMI) and handgrip strength(HGS) among Chinese individuals aged 45 years and above. 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.