Chronic kidney disease (CKD) is a progressive condition linked to sarcopenia, a syndrome characterized by loss of skeletal muscle mass and strength, affecting a quarter of CKD patients globally. Sarcopenia has multiple paths through which it can worsen morbidity and mortality as well as decrease the quality of life in CKD, including systemic inflammation, hormonal imbalances, metabolic changes, and dysbiosis of gut microbiota. There is a regional variation in the criteria set for diagnosis, with two main groups being the European Working Group on Sarcopenia in Older People and the Asian Working Group for Sarcopenia. Management regimes such as nutritional optimization, vitamin D, exercise, correction of metabolic acidosis, and modulation of gut microbiota constitute effective intervention strategies. Emerging therapeutic options include anabolic agents, myostatin inhibitors, and anti-inflammatory treatment options. Future advances such as genomics, proteomics, and personalized medicine will open up new avenues for addressing the complex pathophysiology of sarcopenia. Hence, a comprehensive multidisciplinary approach focused on the specific needs of each patient will be vital in reducing the effects of sarcopenia and improving the situation of people with CKD.

Autonomic nervous system (ANS) dysfunction is prevalent in end-stage kidney disease (ESKD) patients, carrying significant risks for morbidity and mortality. Heart rate variability (HRV) is a simple and non-invasive method to evaluate ANS functions and predict prognoses in specific patient populations. Since there is a lack of a clear understanding of the clinical significance of HRV in predicting prognoses in ESKD patients, an updated review on this topic is urgently warranted. The clinical significance of HRV in dialysis patients includes its associations with metabolic syndrome, nutritional status, intradialytic hypotension, vascular access failure, major adverse cardiovascular events, and mortality. These findings underscore the essential role of the autonomic reserve, which might denote the elevation of ANS activity as a response to external stimulus. Patients with a higher level of sympathetic activity at the resting stage, but who are unable to adequately elevate their sympathetic activity under stress might be susceptible to a worse outcome in critical circumstances. Further applications of HRV include HRV biofeedback, risk classification, and real-time HRV monitoring. Overall, HRV is an optimal tool for predicting prognoses in dialysis patients. Further study is encouraged in order to gain a clearer understanding of the clinical significance and application of HRV, and thereby enhance the care of ESKD patients.

In chronic kidney disease (CKD), protein degradation outweighs protein synthesis, leading to imbalanced cellular protein turnover and a loss of protein and cell mass im-pairing tissue function. Sarcopenia, characterized by the progressive loss of skeletal muscle mass and strength, is a significant complication in CKD. In light of limited articles comprehensively synthesizing the clinical knowledge on sarcopenia, this narrative review explores the pathophysiological mechanisms linking CKD and sarcopenia, including metabolic, hormonal, inflammatory, and nutritional factors. Current diagnostic criteria and highlights of the role of gut microbiota dysbiosis and miRNA alterations in muscle wasting are also discussed. This review predominantly incorporates viewpoints from research from the past and a few classic papers to support the stance of this research. Therapeutic strategies are multifaceted, encompassing nutritional interventions, exercise, anabolic agents, vitamin D supplementation, and correction of metabolic acidosis. Emerging therapies targeting the gut-muscle axis and epigenetic modifications are also considered. Despite advancements, sarcopenia remains un-der-recognized and undertreated in CKD patients. Future research should focus on understanding the molecular pathways of sarcopenia, identifying novel biomarkers for early detection, and developing personalized treatment strategies. Addressing barriers to exercise and nutritional interventions is critical for successful implementation. Overall, sarcopenia in CKD is a multifaceted condition, involved in an interplay between metabolic, hormonal, inflammatory, and nutritional factors. Such mechanisms require comprehensive management strategies in practice, especially through nutritional interventions, pharmaco-logical approaches, and emerging therapies targeting the gut-muscle axis and epigenetic modifications. This review highlights the complex interplay of these mechanisms and underscores the importance of comprehensive management strategies. Nutritional interventions, including adequate protein and vitamin D supplementation and regular physical activity, are essential for mitigating muscle wasting. Pharmacological approaches, such as anabolic agents and anti-inflammatory treatments, show promise but require further research to establish optimal regimens. Emerging therapies targeting the gut-muscle axis and epigenetic modifications offer new avenues for treatment.