Effects of the rotigotine transdermal patch versus oral levodopa on swallowing in patients with Parkinson's disease

Objectives: Abnormal swallowing or dysphagia is a potentially fatal symptom in Parkinson's disease (PD) and is characterized by frequent silent aspiration, which is an unrecognized risk for aspiration pneumonia. While the effects of oral levodopa on swallowing functions remain controversial, several small-scale studies have reported that rotigotine transdermal patch seems effective. The different effects between levodopa and rotigotine may be attributed to continuous dopaminergic stimulation (CDS), however, the absence of direct comparative evidence precludes conclusion. Methods: In the present retrospective open-label study of 50 patients with PD, swallowing functions were assessed via videofluoroscopic (VF) examination before and after treatment. Treatment included 2 mg/day rotigotine transdermal patch (N = 29) or 200 mg/day oral levodopa with carbidopa (N = 21) in drug-naive and add-on groups of patients. Results: Rotigotine more consistently improved all measures assessed via VF examination. Such effects were similar to those in the drug-naive and add-on groups. Improvement and responder rates of certain measures were significantly higher in the rotigotine group than in the levodopa group. Conclusions: Our finding that rotigotine (levodopa equivalent dose = 60 mg) was more consistently effective than 200 mg/day oral levodopa suggests that CDS is more important in improving swallowing functions.