Swallowing Characteristics and Water Swallow Capacity in Patients with Parkinsonism.

Prevalence and characteristics of dysphagia (including aspiration) in patients with parkinsonism is variable, depending on type of assessment, diagnosis, disease stage and duration. The aim of this study was to further evaluate dysphagia characteristics in patients with different types of parkinsonism with both instrumental (Flexible Endoscopic Evaluation of Swallowing, FEES) and non-instrumental (Timed Water Swallow Test, TWST) assessments. Swallowing characteristics in 74 patients with parkinsonism were prospectively assessed using FEES and TWST. Statistics employed were (a) Spearman rank correlation to measure correlation between dysphagia results and Parkinson subtypes, disease severity and duration and (b) the non-parametric tests Mann Whitney U and Kruskal Wallis to measure difference between groups. Dysphagia was common, with 50 (67.6%) of the patients demonstrating a mild-severe Dysphagia Outcome Severity Scale (DOSS, level 1-5). During FEES, 42% aspirated and 68% of these had silent aspiration. Aspiration was seen more frequently with increased disease severity as per Hoehn and Yahr (H&Y) (r = .459, p = < 0.001) and disease duration (r = .269, p = .021). Thin liquid (IDDSI level 0) was the most common consistency to aspirate, and the frequency of aspiration decreased with thicker liquids. Dysphagia and aspiration are common in all subgroups of parkinsonism and seen in early stages of H&Y and within the first year of disease duration. Hence, it is recommended that these patients are evaluated early for optimal management and to avoid aspiration-related complications.