Non-invasive assessment determine the swallowing and respiration dysfunction in early Parkinson's disease.

Introduction: Dysphagia is common among patients with Parkinson's disease. Swallowing and its coordination with respiration is extremely important to achieve safety swallowing. Different tools have been used to assess this coordination, however the results have been inconsistent. We aimed to investigate this coordination in patients with Parkinson's disease using a non-invasive method.

Methods: Signals of submental muscle activity, thyroid cartilage excursion, and nasal airflow during swallowing were recorded simultaneously. Five different water boluses were swallowed three times, and the data were recorded and analyzed.

Results: Thirty-seven controls and 42 patients with early-stage Parkinson's disease were included. The rates of non-expiratory/expiratory pre- and post-swallowing respiratory phase patterns were higher in the patients than in the controls (P < 0.001). The rates of piecemeal deglutition when swallowing 10-ml and 20-ml water boluses and overall were also significantly higher in the patients (all P < 0.001). There were differences in oropharyngeal swallowing parameters between the patients and controls, including a pharyngeal phase delay with longer total excursion duration and excursion time in the patients swallowing small water boluses (1 ml, 3 ml and 5 ml), but no difference in the length of swallowing respiratory pause.

Conclusion: Oropharyngeal swallowing and its coordination with respiration are affected in patients with early-stage Parkinson's disease, and safety compensation mechanisms were used more than efficiency during swallowing. The results of this study may serve as a baseline for further research into new treatment regimens and to improve the management of swallowing in patients with Parkinson's disease.