Unlocking diagnosis of sarcopenia: The role of circulating biomarkers - A clinical systematic review

Sarcopenia, the gradual loss of muscle mass, strength, and function with age, poses a significant risk to older adults, making early diagnosis crucial for preventing disability and enhancing quality of life. Biomarkers are vital for the early detection, monitoring progression, and assessing the efficacy of treatments for sarcopenia, offering a detailed evaluation of muscle health. This systematic review examined the clinical potential of circulating biomarkers in sarcopenia by analyzing studies up to May 2024 from PubMed, Scopus, Web of Science. A total of 45 studies involving 641,730 patients were reviewed, revealing notable biomarker differences between sarcopenic and non-sarcopenic individuals. Sarcopenic patients exhibited lower levels of certain microRNAs, hemoglobin, albumin, and anti-inflammatory factors, alongside higher levels of red and white blood cells, pro-inflammatory factors, growth factors, matrix proteins, free thyroxine, cortisol, and adiponectin. Additionally, they had lower levels of irisin, free triiodothyronine, and insulin, with reduced phosphatidylcholines and elevated spermidine. The studies were generally of fair to good quality, but due to heterogeneity, a meta-analysis was not feasible. The review underscores the need for standardized biomarkers and diagnostic criteria and suggests that improving outcomes for sarcopenic patients may involve addressing inflammation, metabolic, and hormonal issues through nutrition, medication, and exercise.