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

Summary

The study addresses a critical knowledge gap regarding the relationship between serum uric acid (UA) levels and sarcopenia, particularly in the Chinese population, where such an association has not been comprehensively explored.

Abstract

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.

Introduction

Sarcopenia is a degenerative condition that affects the skeletal muscles, leading to a gradual loss of muscle mass. It is linked with adverse consequences, including falls, functional deterioration, frailty, and mortality^1,2,3, thereby emerging as a substantial global public health concern. In the past, sarcopenia was often regarded as an old-age disease, but recent studies have found that due to long-term bad living habits and aging, the muscle mass of some middle-aged people has decreased significantly, and the incidence of sarcopenia among them should not be underestimated....

Protocol

The China Health and Retirement Longitudinal Study (CHARLS) was approved by the Institutional Review Board (IRB) of Peking University, with approval numbers IRB00001052-11014 and IRB00001052-11015. All participants provided informed consent before participating in the study, which was in line with ethical standards and the Declaration of Helsinki. This ensures that the data used from CHARLS complies with ethical research guidelines, including confidentiality and informed participation requirements.

Study population
The data for this study come from the CHARLS survey conducted by the National Development Research Insti....

Results

Characteristics of participants
This study included 10,938 Chinese participants aged 45-94 years, among whom the weighted prevalence of sarcopenia was 6.68%. The study cohort was stratified into four groups based on serum uric acid quartiles: Q1: ≤3.90 mg/dL, Q2: 4.00-4.70 mg/dL, Q3: 4.80-5.60 mg/dL, Q4: ≥5.70 mg/dL. Table 1 presents the weighted baseline characteristics across serum uric acid quartiles. The findings indicated a progressive increase in the weighted average age and BM.......

Discussion

A cross-sectional study was conducted using nationally representative data to evaluate the association between UA and sarcopenia diagnosed using the AWGS 2019 algorithm among middle-aged and older Chinese adults. In this study, participants were Chinese adults aged 45-94 years, and their prevalence of sarcopenia was 6.68%. After adjusting for confounders, it was found that serum UA level was inversely associated with sarcopenia. There was a significant positive correlation between the quartile groups of serum UA levels a.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
China Health and Retirement Longitudinal Study (CHARLS)	Peking University	https://charls.pku.edu.cn/.
EmpowerStats	https://www.empowerstats.net/en/	Version 2.0
R	https://www.r-project.org/	Version 4.2.2