title: Evidence-based treatment of voice and speech disorders in Parkinson disease.
abstract: OBJECTIVE
  Voice and speech impairments are present in nearly 90% of people with Parkinson disease and negatively impact communication and quality of life. This review addresses the efficacy of Lee Silverman Voice Treatment (LSVT) LOUD to improve vocal loudness (as measured by vocal sound pressure level vocSPL) and functional communication in people with Parkinson disease. The underlying physiologic mechanisms of Parkinson disease associated with voice and speech changes and the strength of the current treatment evidence are discussed with recommendations for best clinical practice.
  
  
  RESULTS
  Two randomized control trials demonstrated that participants who received LSVT LOUD were significantly better on the primary outcome variable of improved vocSPL posttreatment than alternative and no treatment groups. Treatment effects were maintained for up to 2 years. In addition, improvements have been demonstrated in associated outcome variables, including speech rate, monotone, voice quality, speech intelligibility, vocal fold adduction, swallowing, facial expression and neural activation. Advances in technology-supported treatment delivery are enhancing treatment accessibility.
  
  
  CONCLUSIONS
  Data support the efficacy of LSVT LOUD to increase vocal loudness and functional communication in people with Parkinson disease. Timely intervention is essential for maximizing quality of life for people with Parkinson disease.
authors.affiliation: aDepartment of Communicative Disorders, University of Rhode Island, Kingston, Rhode Island bUniversity of Colorado, Boulder, Colorado cColumbia University, New York, New York dNational Center for Voice and Speech, Denver, Colorado, USA.
authors.forename: Leslie A
authors.initials: LA
authors.lastname: Mahler
authors.forename: Lorraine O
authors.initials: LO
authors.lastname: Ramig
authors.forename: Cynthia
authors.initials: C
authors.lastname: Fox
mesh_terms: D019317:Evidence-Based Medicine; D006801:Humans; D010300:Parkinson Disease / Q000150:complications* / Q000503:physiopathology; D011788:Quality of Life; D013064:Speech Disorders / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy*; D014832:Voice Disorders / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy*