Scoping review of 49 studies (1,388 patients) on Parkinson’s-related dysphonia found voice therapy to have the most consistent, statistically significant benefits, while other approaches (DBS, drugs, surgical) showed heterogeneous or mixed effects.

Although it does not address disease-modifying biology, the paper identifies an evidence-backed, actionable symptomatic intervention (voice therapy) that improves quality of life and underscores the need for standardized outcome metrics and studies of combined therapies in PD care.

OBJECTIVE: Dysphonia in patients with Parkinson's Disease (PD) negatively impacts quality of life. Treatment options are evolving and include both invasive and non-invasive interventions. The present study aims to assess current therapies and their effectiveness through a scoping review of the literature. DATA SOURCES: PubMed, Ovid, and Embase. REVIEW METHODS: Three databases were searched for articles through 2023 pertaining to treatment of PD-related dysphonia in accordance with PRISMA guidelines. Included studies were reviewed to extract demographic information, treatment techniques, and outcomes. Of 277 studies reviewed, 49 publications met inclusion criteria with a total of 1388 patients. RESULTS: Treatments were categorized into groups: voice therapy, pharmacologic intervention, deep brain stimulation (DBS), vocal fold augmentation, neurosurgical intervention, and dietary modification. Measures reported to assess outcomes were heterogenous across studies. Voice therapy had the highest number of studies with statistically significant results, totaling 18 studies. Other treatments, including DBS, demonstrated improvement in systemic symptoms with worsening of voice symptoms. CONCLUSION: The literature of current therapeutic options for PD patients with dysphonia is heterogenous; however, voice therapy remains standard of care. Further studies should emphasize standardization of voice metrics to permit head-to-head comparisons across treatment modalities. There is also an opportunity to leverage combining therapies for PD patients, but optimization of such regimens requires further investigation.