Progression of Self-Perceived Speech and Swallowing Impairment in Early Stage Parkinson's Disease: Longitudinal Analysis of the Unified Parkinson's Disease Rating Scale

Abstract

Purpose: The purpose of this study was to investigate the presence and progression of self-perceived speech and swallowing impairments in newly diagnosed people with Parkinson's disease (PD) longitudinally across 6 years. Method: Longitudinal data from the Parkinson's Progression Markers Initiative were analyzed across six consecutive years in a cohort of 269 newly diagnosed people with PD, and a subset of those ( n = 211) who were assessed at every time point across the 6 years. Dependent variables included self-perceived ratings of speech and swallowing impairment severity from the Unified Parkinson's Disease Rating Scale. Patient-centered factors of age at diagnosis and motor phenotype were also assessed to determine if they were related to the change in self-perceived speech and swallowing impairments. Results: Overall, self-perceived speech and swallowing impairments were present in newly diagnosed people with PD, although over time, the degree of severity for both remained in the mild range. However, the rate of change over time was significant for perceived speech impairment, F (5.5, 1158.8) = 21.1, p < .001), and perceived swallowing impairment, F (5.2, 1082.6) = 8.6, p < .001. Changes for speech and swallowing impairment were both in the direction of progressive severity. There were no effects of age at diagnosis or motor phenotype on the degree of change for either speech or swallowing. Conclusions: Self-perceptions of speech and swallowing impairment changed significantly over time in newly diagnosed people with PD (PWPD). Consistent with existing literature, self-perceptions of speech impairment were rated as more severe than those of swallowing impairment. These findings reveal that even in the early years postdiagnoses, PWPD are experiencing changes to speech and swallowing function, albeit within the mildly severe range. The presence of self-perceived mild speech and swallowing impairments in the initial years postdiagnosis may support the need for intervention to improve and or sustain function over time.