Soluble interleukin 2 receptor is risk for sarcopenia in Men with high fracture risk.

Background & Aims: Sarcopenia is an age-related disease that increases the risk of falls and fractures in older adults. However, there is no blood biochemical marker to help to predict or diagnose sarcopenia in clinical practice. Soluble interleukin 2 receptor (sIL-2R) was reported to be associated with muscle satellite cell dysfunction which played an important role in the pathogenesis of sarcopenia. Thereby, we aimed to explore the association between serum sIL-2R and sarcopenia in older adults at high risk of fractures.

Methods: A total of 429 hospitalized older adults (age ≥55 years) were enrolled in this cross-sectional study (mean age ​= ​66.62 ​± ​6.59 years; 62.7% female). Logistic regression analysis was performed to assess the association of sIL-2R with sarcopenia, muscle mass, muscle strength, and physical performance, respectively. The optimal models for the diagnosis of sarcopenia and low hand grip strength (HGS) were established by multivariable binary logistic regression analysis with backward selection, and further were evaluated for the diagnostic values by receiver operating characteristic (ROC) curve.

Results: Higher sIL-2R levels were found in sarcopenia than no-sarcopenia group in male (median 421 U/mL (interquartile range [IQR] 217 U/mL) vs median 362 U/mL (IQR 157 U/mL); n ​= ​77 vs 83;  ​< ​0.01). Compared to the lowest sIL-2R tertile, the highest tertile of sIL-2R was independently associated with the risk of low HGS (odds ratio [OR] 4.608, 95% confidence interval [CI] 1.673-12.695) and the risk of sarcopenia (OR 3.306, 95% CI 1.496-7.302) in men. ROC curves revealed that the Area Under the Curve (AUC) of the optimal models for diagnosing sarcopenia and low HGS was 0.752 and 0.846.

Conclusion: Our results suggest that serum sIL-2R is the independent risk factor for sarcopenia and low muscle strength only in men. sIL-2R may be developed to be a biochemical marker for sarcopenia and low muscle strength diagnoses in older men at high risk of fractures, but more prospective studies are needed to prove it.

The Translational Potential Of This Article: Our results showed that the highest tertile of sIL-2R was independent of low risk of HGS and sarcopenia in men, compared to the lowest tertile. As the population ages, sIL-2R may become a potential diagnostic tool for predicting low HGS and sarcopenia among men at high risk of fractures.