Objectives-To assess long term (24 months) eVects of the Lee Silverman voice treatment (LSVT®), a method designed to improve vocal function in patients with Parkinson's disease. Methods-Thirty three patients with idiopathic Parkinson's disease were stratified and randomly assigned to two treatment groups. One group received the LSVT®, which emphasises high phonatoryrespiratory eVort. The other group received respiratory therapy (RET), which emphasises high respiratory eVort alone. Patients in both treatment groups sustained vowel phonation, read a passage, and produced a monologue under identical conditions before, immediately after, and 24 months after speech treatment. Change in vocal function was measured by means of acoustic analyses of voice loudness (measured as sound pressure level, or SPL) and inflection in voice fundamental frequency (measured in terms of semitone standard deviation, or STSD).Results-The LSVT® was significantly more eVective than the RET in improving (increasing) SPL and STSD immediately post-treatment and maintaining those improvements at 2 year follow up. Conclusions-The findings provide evidence for the eYcacy of the LSVT® as well as the long term maintenance of these eVects in the treatment of voice and speech disorders in patients with idiopathic Parkinson's disease. (J Neurol Neurosurg Psychiatry 2001;71:493-498)

This study investigated the effect of two forms of intensive speech treatment, (a) respiration (R) and (b) voice and respiration (Lee Silverman Voice Treatment [LSVT]), on the speech and voice deficits associated with Idiopathic Parkinson disease. Forty-five subjects with Idiopathic Parkinson disease completed extensive pretreatment neurological, otolaryngologicai, neuropsychological, and speech assessments. All subjects completed 16 sessions of intensive speech treatment, 4 times a week for 1 month. Pre- and post-treatment measures included intensity and maximum duration during sustained vowel phonation. Intensity, habitual fundamental frequency, fundamental frequency variability, and utterance and pause duration were measured during reading of the “Rainbow Passage” and conversational monologue as well. Family and subject self-ratings were completed pre- and post-treatment for the perceptual variables loudness, monotonicity, hoarseness, overall intelligibility, and initiation of conversation. Significant pre- to post-treatment improvements were observed for more variables and were of greater magnitude for the subjects who received the voice and respiration treatment (LSVT). Only subjects who received the LSVT rated a significant decrease post-treatment on the impact of Parkinson disease on their communication. Correlations between descriptive prognostic variables (i.e., stage of disease, speech/voice severity rating, depression, and time since diagnosis) and magnitude of treatment-related change indicated these factors did not significantly predict treatment effectiveness. These findings suggest that intensive voice and respiration (LSVT) treatment, focusing on increased vocal fold adduction and respiration, is more effective than respiration (R) treatment alone for improving vocal intensity and decreasing the impact of Parkinson disease on communication.

This study assessed the impact of the Lee Silverman Voice Treatment (LSVT®) on vocal loudness [sound pressure level (SPL)] in a group of dysarthric individuals with idiopathic Parkinson's disease (IPD). Pre‐ to post‐treatment changes in SPL in the treated group were compared with changes in voice SPL during the same time in two control groups: individuals with IPD not treated with the LSVT® and in non‐disordered individuals, age‐matched to the patients. All subjects produced the same voice and speech tasks—sustaining vowel phonation, reading the “Rainbow Passage,” producing a short monologue, and describing a picture. These tasks were recorded at three different occasions: just prior to treatment, just after treatment, and 6 months following treatment. The individuals treated with LSVT® increased voice SPL from baseline to post‐treatment by an average of 8 dB and from baseline to 6 months follow‐up by an average of 6 dB. These changes were statistically significant and perceptibly audible. No significant changes in SPL were observed in the control groups during the time corresponding to the treatment and follow‐up. Differences in SPL between the treated and untreated patients at post‐treatment and follow‐up were statistically significant for all voice and speech tasks. These findings, along with others, provide additional support for the efficacy of the LSVT®. Mov. Disord. 16:79–83, 2001. © 2001 Movement Disorder Society.

The purpose of this study was to evaluate the long-term (12 months) effects of two forms of speech treatment on the speech and voice deficits that occur in Parkinson's disease. Thirty-five patients with idiopathic Parkinson's disease were assigned to one of two speech treatment groups: voice and respiration (The Lee Silverman Voice Treatment [LSVT]) or placebo (respiration) treatment. Vocal intensity data from before, immediately after, and at 6 and 12 months after speech treatment revealed statistically significant differences between the treatment groups. Only subjects in the LSVT group improved or maintained vocal intensity above pretreatment levels by 12 months after treatment. The placebo group had statistically significant deterioration of vocal intensity levels from before to 12 months after treatment during conversational monologue. The LSVT group did not deteriorate to levels below pretreatment in vocal intensity over the 12-month period. This study is the first to document the short-and long-term effects of intensive speech treatment (LSVT), which focuses on the voice, for patients with Parkinson's disease compared with a placebo speech treatment group.

Thirty-five individuals with idiopathic Parkinson’s disease were enrolled in speech treatment. Twenty-two were enrolled in a high-effort phonatory-respiratory treatment program (Lee Silverman Voice Treatment, LSVT^®) and 13 were enrolled in a high-effort respiratory treatment program (RET). Perceptual judgments of speech loudness and quality were made independently by 6 listeners on recordings of the ‘Rainbow Passage’. These recordings had been obtained just before treatment (pre) and at 12 months’ follow-up (FU12). The speech samples in the LSVT group, but not in the RET group, were significantly more likely to be perceived ‘louder’ and ‘better quality’ at FU12 than at pre (p < 0.0001). These findings, along with others, suggest that the long-term effects of the LSVT are perceptible, clinically significant and treatment-specific.