The Relationship between the Risk of Sarcopenia in the Elderly and Autonomic Nervous System Balance

Elderly people with sarcopenia experience symptoms related to dysfunction in the autonomic nervous system (ANS), including rapid or irregular heartbeat, dizziness, and fluctuations in blood pressure. These symptoms may be a result of immune system activation and the impact of the disease, leading to alterations in certain aspects of ANS regulation. There is limited research that discusses the relationship between these factors. Therefore, we investigated the correlation between the risk of sarcopenia and the balance of the autonomic nervous system. The participants included 87 females and 25 males aged between 60 and 79 years old, who were assessed for sarcopenia risk including walking speed, grip strength, muscle mass, and the Appendicular Skeletal Muscle Mass Index (ASM). The collected data were analyzed using descriptive statistics, t-tests, one-way ANOVA, and Pearson correlations. The results showed the following: (1) Individuals at a high risk of sarcopenia displayed a slightly greater degree of autonomic nervous system imbalance compared to those at low risk. (2) In the time-domain analysis, sympathetic nervous system activity was higher in males than in females, whereas parasympathetic nervous system activity exhibited the opposite trend. In the frequency-domain analysis, heart rate variability was higher in females than in males, and both genders met the criteria for sarcopenia risk assessment. (3) There were no significant differences in heart rate variability indices among different sarcopenia risk groups. (4) Different levels of sarcopenia risk showed a significant correlation with ANS. Individuals at a higher risk demonstrated an imbalance, while those at a lower risk displayed a more balanced state. Overall, the results of this study confirmed the correlation between sarcopenia risk and heart rate variability among the elderly, further emphasizing the importance of the autonomic nervous system in sarcopenia risk.