Association Between Serum High Sensitivity C-Reactive Protein Levels and Low Muscle Strength Among Korean Adults

Chronic low-grade inflammation is increasingly recognized as a contributor to age-related muscle loss and functional decline, yet its association with muscle strength in Asian populations remains underexplored. Therefore, this study aimed to investigate the relationship between high-sensitivity C-reactive protein (hsCRP) and low muscle strength in Korean adults.

Data were obtained from 14,354 participants aged ≥ 19 years in the 7th Korea National Health and Nutrition Examination Survey (KNHANES VII, 2016-2018). Low muscle strength was defined as handgrip strength < 28 kg for men and <18 kg for women, and serum hsCRP levels were categorized as normal (<1.0 mg/L), elevated (1.0-3.0 mg/L), and high (≥3.0 mg/L). Multivariable logistic regression was used to assess the association between serum hsCRP level and low muscle strength with adjustment for possible confounders.

Among Korean adults, 27.7% had elevated or high hsCRP level, and low muscle strength was prevalent in older adults ≥ 65 years (men 22.7%, women 34.1%). Elevated hsCRP was associated with increased odds of low muscle strength in middle-aged women 40-64 years (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.04-2.09) and in older women ≥ 65 years (OR, 1.34; 95% CI, 1.04-1.74). High hsCRP was associated with higher risk in older men (OR, 1.71; 95% CI, 1.06-2.75) and older women (OR, 1.66; 95% CI, 1.14-2.42).

Higher hsCRP levels were independently associated with low muscle strength in middle-aged women and older adults. Downregulating inflammation through nutritional strategies could help prevent muscle decline with aging.