Daily Phonatory Activity of Individuals With Parkinson's Disease

This study evaluated the amount of phonatory activity of Persons with Parkinson disease (PwPD) compared to adults without Parkinson's disease measured over 3 days. The relationship between the amount of phonatory activity and Voice Handicap Index (VHI) total score was assessed as were differences in voicing activity across 3 days of data collection.

Fifteen PwPD receiving dopaminergic medication and fifteen age and sex matched adults without Parkinson's disease completed the VHI and then wore a VocaLog vocal monitor (VM) for 3 consecutive days. From the VM data, the number of 1-second windows with dB sound pressure level > 0 were summed as a measure of phonatory activity (PA) and reported relative to the time the VM was worn (%PA).

The percentage of time the VM was worn did not differ between groups or across days. The PwPD had statistically significantly fewer minutes of PA per day than controls (F = 21.782, P < 0.001) by 54 minutes on average. The %PA also differed significantly (F = 31.825, P < 0.001) with a mean of 11.1% for PwPD and 18.6% for controls. Neither PA nor %PA differed across the 3 days of vocal monitoring. VHI total score was significantly correlated with PA (r = -0.436, P = 0.016) and %PA (r = -0.534, P = 0.002) for all participants.

The results indicate that PwPD engaged in less verbal communication in their daily environment compared to adults without Parkinson's disease. The findings support reports in the literature indicating that PwPD often have reduced communication participation. Measures such as %PA could serve as a quantifiable metric in future studies assessing communication changes in PwPD as a function of disease progression or therapeutic interventions.