Auditory-Perceptual Analysis of Speech Outcomes Following HiCommunication Intervention in Parkinson's Disease-A Secondary Analysis of a Randomized Controlled Trial.

PURPOSE

HiCommunication is a group intervention for Parkinson's disease (PD) targeting speech and communication. This study investigated its effects on speech and voice using auditory-perceptual analyses, following previous evaluation with acoustic outcomes, and examined correlations between auditory-perceptual parameters and acoustic measures.

METHODS

Ninety-five participants with mild-to-moderate PD were randomized to either HiCommunication or an active control intervention. Experienced speech and language pathologists rated 21 speech and voice parameters from recordings collected preintervention, postintervention, and at a 6-month follow-up. Intention-to-treat (ITT) analyses-where all participants are analyzed in their original groups regardless of adherence-used linear or Hurdle multilevel models with imputed missing values, complemented by per-protocol analyses. Correlation analyses examined the relationship between acoustic measures (voice sound level, Acoustic Voice Quality Index, and harmonics-to-noise ratio) and corresponding auditory-perceptual parameters.

RESULTS

In the ITT analyses, loudness decay showed a significant group effect (b = 1.66, P = 0.032) and group-by-time interaction (b = 0.52, P = 0.034), confirmed in intervention completers. Additional group-by-time effects in completers were observed for imprecise articulation (b = 0.70, P = 0.016) and vocal fry (b = 0.58, P = 0.003). Weak-to-strong correlations were observed between auditory-perceptual and acoustic measures.

CONCLUSION

The findings highlight the potential benefits of HiCommunication in improving loudness, articulation, and voice quality (ie, reduced vocal fry) in individuals with PD, particularly among completers of the intervention. However, effects on broader auditory-perceptual parameters of speech deviation were limited, and the perceptual ratings appeared less sensitive than acoustic measures in detecting subtle changes associated with mild hypokinetic dysarthria. These results underscore the value of combining auditory-perceptual and acoustic assessments in evaluating speech interventions and point to the need for strategies to support adherence and optimize outcomes.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03213873.