Voice quality outcomes of idiopathic Parkinson's disease medical treatment: A systematic review

Abstract

The majority of studies supported that VQ assessments remain useful as outcome measures of the effectiveness of medical treatment and could be helpful for the IPD diagnosis based on L-Dopa challenge testing. Further controlled studies using standardised and transparent methodology for measuring acoustic parameters are necessary to confirm the place of each tool in both IPD diagnosis and treatment evaluation.

Orofacial Strength and Voice Quality as Outcome of Levodopa Challenge Test in Parkinson Disease

“…The misdiagnosis of IPD may be related to the phenotypic heterogeneity in both the disease and the levodopa responsiveness, as well as the subjectivity of the diagnosis approach, which is still based on the neurologist clinical examination 15 . Thus, over the past decades, an increasing number of studies have been conducted for investigating the reliability of some objective approaches evaluating the motor changes of IPD from pre‐ to post‐LCT, for example, speech and voice quality measurements 4,8–11,16 …”

“…Shimmer is an acoustic measurement of the short‐term intensity perturbation of the voice quality. Interestingly, in a recent systematic review of studies assessing voice quality changes over the LCT, shimmer has been identified as the best acoustic parameter for exhibiting the laryngeal muscle improvement from pre‐ to post‐LCT 4 . Thus, the realization of the acoustic measurements is easy and reliable in laryngology office.…”

“…15 Thus, over the past decades, an increasing number of studies have been conducted for investigating the reliability of some objective approaches evaluating the motor changes of IPD from pre-to post-LCT, for example, speech and voice quality measurements. 4,[8][9][10][11]16 The first part of the study reports that early-stage IPD patients have both subjective and objective voice quality impairments compared to healthy individuals. From an objective standpoint, healthy individuals exhibited better values of noise-related, tremor, F0 shortand mid-term, and intensity short-term parameters than IPD patients.…”

“…1 According to some reports, 60% to 90% of patients have subtle voice and speech impairments at the time of diagnosis. [2][3][4] In practice, the clinical diagnosis is often challenging in the onset of the disease, when motor features are subtle. 5 For these doubtful cases, the neurologist may make an acute levodopa challenge test (LCT), which consists of the administration of a standardized dose of levodopa and the objectification of the reduction of the motor symptoms, for example, rigidity, bradykinesia, and resting tremor.…”

“…Currently, the IPD diagnosis is mainly based on the clinical examination of patients who present muscle rigidity, tremors, and alterations in speech and gait 1 . According to some reports, 60% to 90% of patients have subtle voice and speech impairments at the time of diagnosis 2–4 . In practice, the clinical diagnosis is often challenging in the onset of the disease, when motor features are subtle 5 .…”