Swallowing abnormalities and their response to treatment in Parkinson's disease

We investigated swallowing abnormalities in patients with Parkinson's disease, the relationship between these abnormalities and general parkinsonian signs, as well as the response to therapy. Twenty patients and 13 controls were evaluated with clinical rating scales and modified barium swallows before and after oral levodopa (in combination with carbidopa). Fifteen patients, but only 1 control, had abnormal swallows (chi 2 = 11.722, df = 1, p less than 0.001). Abnormalities included disturbances of oral and pharyngeal phases of swallowing. Patients without dysphagia frequently had abnormal swallows, including silent aspiration. Seven patients had improved swallowing after levodopa, whereas 1 worsened. Improvement in general parkinsonian signs was not a reliable indicator of improved swallowing.