Swallowing function in patients with multiple-system atrophy with a clinical predominance of cerebellar symptoms (MSA-C)

We investigated the swallowing function of 21 patients with multiple system atrophy with a clinical predominance of cerebellar symptoms (MSA-C) by videofluoroscopy (VF). Twenty-six VF examinations were performed at various time points, and they were divided into three groups according to the duration following disease onset: Group A had 1 to 3 years following disease onset (the early stage of the disease), group B had 4 to 6 years following disease onset (the middle stage of the disease), and group C had more than 7 years following disease onset (the late stage of the disease). Swallowing function in the oral phase became gradually disturbed over the progression of MSA. Delayed bolus transport from the oral cavity to the pharynx was already seen in 50% of the patients in group A, and it was seen in more than 85% of the patients in group C. Bolus holding in the oral cavity was slightly disturbed in group A, but it was seen in 57% of the patients in group C. Our study shows that parkinsonism is related to swallowing dysfunction in MSA, but cerebellar dysfunction also affects coordination of the tongue; bolus transport in the oral cavity was disturbed in the early stage of disease. Progression of cerebellar dysfunction and overlapped parkinsonism will worsen tongue movement, and in the late stage of the disease, swallowing function of the oral phase (bolus transport and bolus holding) was remarkably disturbed. Swallowing function in the pharyngeal phase was not significantly correlated to the duration of the disease; however, our study showed that swallowing function in the pharyngeal phase was not assessed fully by VF examination in MSA-C only. Combination with other examinations, such as manometry and electromyography, may be useful, especially in the late stage of the disease. In addition, an analysis concerning the relationship between aspiration seen on VF examination and a history of aspiration pneumonia in MSA-C patients suggested that the sensory system at the larynx and trachea should also be assessed in patients in the late stage of MSA-C.