Changes in Timing of Swallow Events in Parkinson's Disease.

Objectives:: The prevalence of Parkinson's disease (PD) increases as the population ages. Dysphagia and subsequent aspiration pneumonia are common causes of morbidity and mortality in those with PD. To maximize the benefit of swallowing therapy, protocol design should be based on an understanding of the physiologic swallowing deficits present in the PD population. The aim of this study was to compare the timing of swallow events in a cohort of patients with PD with that in normal age-matched control subjects to characterize variations in the coordination of structural displacement and bolus movement that may contribute to dysphagia.

Methods:: This retrospective study included 68 adults with diagnoses of PD. Liquid bolus swallows during modified barium swallow studies were analyzed and compared with those from an age- and sex-matched cohort of 48 adults without PD.

Results:: Patients with PD were significantly slower in initiating and completing airway closure. Hyoid elevation was prolonged in this patient population.

Conclusions:: Patients with PD demonstrate slower initiation of airway closure and a delay in relaxation of hyoid elevation during swallow. Delays increased with larger boluses. These findings may be related to impaired pharyngeal sensation and increased muscular rigidity. The results of this study will be helpful in guiding swallow therapy for patients with PD.