Speech and swallowing symptoms associated with Parkinson's disease and multiple sclerosis: a survey.

A survey of approximately 460 patients with Parkinson's disease (PD) or multiple sclerosis (MS) shows that speech and swallowing difficulties are very frequent within these groups. Seventy percent of the PD patients and 44% of the MS patients had experienced impairment of speech and voice after the onset of their disease. Forty-one percent of the PD patients and 33% of the MS patients indicated impairment of chewing and swallowing abilities. The speech disorder was regarded as one of their greatest problems by 29% of the PD patients and by 16% of the MS patients. Only a small number of patients, 3% of the PD and 2% of the MS group, had received any speech therapy.