Monitoring Progress of Parkinson's Disease Based on Changes in Phonation: a Pilot Study

Hypokinetic dysarthria (HD) is a frequent symptom of idiopathic Parkinson's disease (PD). Although it is hypothesized its progress is tightly linked with changes in other motor/non-motor features of PD, it has not been proved yet. The aim of this work is to employ acoustic analysis of sustained phonation in order to identify significant correlates between phonatory measures and motor/non-motor deficits in a two-year follow-up study. For this purpose, we repeatedly quantified a sustained vowel/a/ in 51 PD patients who were also assessed by 5 common clinical scales. In addition, a multivariate regression model was trained to predict the motor/non-motor deficits in the horizon of two years. Results suggest that mainly instability in vocal folds oscillation increases with the progress of PD and with overall cognitive decline. Based on the acoustic analysis, the change in clinical scores could be predicted with the error in the range of 11.83-19.60 %.