Effects of different side motor impairments at early onset on voice acoustic performance in patients with Parkinson's disease.

Purpose: This study aimed to explore the effects of motor impairments on different sides of the body at early onset in relation to voice acoustic performance in patients with Parkinson's disease. Materials and methods: Participants were classified based on which side (left or right) experienced motor impairments first, as well as the stage (early or late) of the disease. Hoehn-Yahr stages one and two were categorized as early-stage, while stages three and four were categorized as late-stage. Participants were divided into four groups: Group A, left-side early-stage conditions; Group B, left-side late-stage conditions; Group C, right-side early-stage conditions; Group D, right-side late-stage conditions. Participants performed three recording tasks that involved sustained phonation of the vowels/a/,/i/, and/u/. The study analyzed four acoustic parameters: Maximum Phonation Time (MPT), jitter, shimmer, and vF0. Results: An Analysis of Variance revealed that for the acoustic parameters of /a/vF0 and /a/jitter, Group B performed significantly worse than Group A ( Conclusions: The side of motor impairments at early onset is correlated with the severity of voice disorders. Notably, when impairments occur on the left side, the resulting voice disorders become more pronounced as the disease progresses.