Swallowing Pathophysiology in Primary Sarcopenia: A Multimodal Assessment in Older Adults

Primary sarcopenia, characterized by age-related decline in muscle mass and strength, is increasingly recognized as a contributor to oropharyngeal dysphagia in older adults. Understanding its mechanical and functional components is essential for early detection and intervention. This study aimed to investigate early oropharyngeal swallowing impairments in older adults with primary sarcopenia using a multimodal instrumental assessment and to evaluate the utility of combining different objective measures. In this cross-sectional study, swallowing safety and efficiency were assessed using the Dynamic Imaging Grade of Swallowing Toxicity (DIGEST) scale through fiberoptic endoscopic evaluation of swallowing (FEES) in 44 older individuals with primary sarcopenia. Additional assessments included tongue strength measurement, suprahyoid muscle activity using surface electromyography (sEMG), peak cough flow (PCF), and self-perceived swallowing symptoms evaluated using Eating Assessment Tool-10 (EAT-10). According to DIGEST overall score, 20.5% of participants showed no dysphagia (grade 0), while 56.8% had mild (grade 1), and 22.7% had moderate (grade 2) dysphagia. Participants with dysphagia (grades 1-2) showed decreased tongue strength, reduced sEMG amplitudes, longer swallowing durations, and decreased PCF compared to those with grade 0. Although these differences were not statistically significant, a trend toward early functional decline was noted. These findings suggest that in early-stage primary sarcopenia, swallowing safety may be preserved despite mild physiological deficits. This likely reflects the presence of a functional reserve within the swallowing mechanism. However, clinicians should not rely solely on this compensation, as subtle changes may precede clinically significant dysphagia. Early identification and monitoring remain crucial to prevent deterioration in this vulnerable population.