Effect of Levodopa on Speech Dysfluency in Parkinson's Disease

Abstract

Objective Objective: To examine the effect of levodopa medication on speech dysfluency in Parkinson's disease. MethodsMethods: Fifty-one individuals with Parkinson's disease (IWPD) read aloud during offand onmedication states. Total speech dysfluencies were calculated from transcriptions of recorded speech samples. ResultsResults: Severity of speech dysfluency was not significantly related to the severity of motor symptoms, duration of disease, levodopa equivalent dosage, or age. When the IWPD were divided into two groups based on dysfluency severity, there was a significant group-by-medication state interaction. There was a significant correlation between the medication-related change in speech dysfluency and the off-medication severity of speech dysfluency measure (r = −0.46). Conclusions Conclusions:The results of this study indicate that levodopa medication can have a significant effect on speech dysfluency. The beneficial levodopa effect appears to be related to the severity of the off-medication speech dysfluency. Results did not provide strong support for the excess dopamine theory of stuttering in IWPD. A dualistic model of the effects of dopamine on speech fluency in PD is proposed.

Assessment of Parkinson's Disease Medication State through Automatic Speech Analysis

“…Finally, when investigating the effects of Levodopa on developmental stuttering, Anderson et al [14] reported an increase of disfluencies in the spontaneous speech of 1 patient during the ON period. This is in disagreement with the findings of Im et al [15], which examined 51 patients while reading a standard passage. In fact, the authors found an improvement of disfluency in the ON state that was proportional to the severity of speech impairments presented in the OFF state.…”

“…However, while the effects of dysarthria in PD have been deeply investigated, both in drug-naive state and under pharmacological treatment [4][5][6][7][8][9], it is still not clear whether speech analysis could be helpful to differentiate between ON-OFF states induced by pharmacological intake. In fact, the clinical literature presents controversial results on the effect of Levodopa on speech abilities [10][11][12][13][14][15], while no computational studies addressing this topic have been identified in the literature.…”

The clinical meaning of levodopa equivalent daily dose in Parkinson's disease

“…Ikeda et al showed that the increase in L-dopa daily dose was greater in patients without a decline in cognitive function. [58] However, higher total LEDD Clinical meaning of LEDD has been reported on the one hand in patients with speech dysfluencies compared with fluent patients [59] and on the other hand, as a risk factor of executive function decline post-STN-DBS. [60] Concerning psychosis, Lenka et al illustrated that higher total LEDD may not trigger early occurrence of psychosis in PD patients.…”

Voice Analysis to Differentiate the Dopaminergic Response in People With Parkinson's Disease

“…Although Im et al (2019) conclude that the comparison of the PD participants in the ON state vs. OFF state conditions did not reach statistical significance, the last explorations performed recently, based on machine and deep learning by Norel et al (2020); Pompili et al (2020) reported higher accuracies of ON and OFF classification. Norel et al (2020) analyzed voice of PwPD describing a picture, speaking reverse counting, and diadochokinetic rate speech tasks.…”

“…Tykalová et al (2015) found a strong positive correlation between the total cumulative dose of levodopa and the increased occurrence of dysfluent words and stuttering. Likewise, results from Im et al (2019) indicate that levodopa medication can significantly affect speech dysfluency, primarily associated with the severity of the OFF medication. Speech analysis has been done on a standard Rainbow passage reading task.…”