Abstract
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by onset within the upper limb, lower limb, or bulbar musculature. Regardless of site of onset, dysphagia inevitably occurs. This study aimed to examine the course of dysphagia in ALS, and to investigate whether the progression of dysphagia differs by site of onset. Thirty ALS patients were included. For each patient, we collected information on site of disease onset (bulbar or limb onset), duration to initiation of gastrostomy feeding from disease onset, dysphagia onset, course of dysphagia, and course of the respiratory function after dysphagia onset. Patients were divided into two groups based on the site of onset: the bulbar onset group (the BO group, i.e., clinical onset was characterized by dysarthria and/or dysphagia) and the limb onset group (the LO group, i.e., limb weakness was the first symptom). Each survey item was compared between two groups. There were no significant differences in time to initiation of gastrostomy feeding from disease onset between groups (p=0.45). On the other hand, there were significant differences in dysphagia onset, course of dysphagia, and course of the respiratory function after dysphagia onset (p=0.0008, p=0.007, p=0.0002, respectively).Our result suggest that the progression of dysphagia in ALS may differ by site of onset. Compared with bulbar onset ALS patients, progression of dysphagia may be faster in limb onset patients. Moreover, the decline in respiratory function is likely to influence the progression of dysphagia.