Objective: To assess the influence of levodopa on swallowing dysfunction in Parkinson's disease patients.
Methods: A systematic review of the literature and a meta-analysis were performed. All studies referring to levodopa and swallowing dysfunction that provided direct data or data that could be transformed into mean +/- standard deviation were considered for analysis. The primary efficacy variables were Oral Transit Time (OTT), Pharyngeal Transit Time (PTT) for both thin fluids and solids, and aspiration.
Results: Seven studies describing swallowing functions in PD patients using levodopa were found, and five of these matched the inclusion criteria. No clinically meaningful improvement after levodopa intake was noted. Adverse effects were not reported by the authors.
Conclusion: This meta-analysis shows that levodopa intake was not associated with an improvement of swallowing dysfunction in Parkinson's disease patients.