Effectiveness of Speech Language Pathology Interventions in Managing Hypokinetic Dysarthria in Parkinson's Disease: A Comprehensive Systematic Review

• Heba Salama

  Doctorat of Philosophy speech therapist at Alexandria University, Alexandria, Egypt

  Author

Hypokinetic dysarthria is a prevalent non-motor symptom affecting up to 90% of Parkinson's disease (PD) patients, characterized by reduced vocal loudness, monotone speech, and significantly decreased intelligibility. These speech impairments severely impact patients' quality of life, leading to social isolation and depression. This systematic review evaluates the clinical efficacy of intensive speech programs, specifically Lee Silverman Voice Treatment (LSVT LOUD), compared to traditional speech therapy approaches. Following PRISMA guidelines, a comprehensive search was conducted across PubMed, Scopus, Web of Science, and PsycINFO for studies published between January 2010 and July 2024. The analysis of 28 eligible studies demonstrated that LSVT LOUD achieves significant and clinically meaningful improvements in sound pressure level (increases of 5-10 dB) and speech intelligibility (20-30% improvement). Furthermore, telehealth delivery models show non-inferior outcomes compared to traditional face-to-face sessions, enhancing accessibility. The findings indicate that intensive speech programs act as effective neurobehavioral interventions that stimulate neuroplasticity rather than mere muscle training. Practical implications suggest that policymakers should mandate insurance coverage for these intensive programs to reduce the overall healthcare burden. In conclusion, intensive speech-language pathology interventions are highly effective for managing hypokinetic dysarthria in PD. However, there is an urgent need for culturally adapted versions, particularly for non-English speakers, and further integration with emerging technologies like AI and mobile applications to ensure long-term maintenance and personalized treatment.

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