Effects of vocalization training on drooling severity in Parkinson's disease

Objective To investigate the effect of vocalization training in improving drooling in patients with Parkinson's disease (PD). Methods A total of 60 PD patients from August 2018 to July 2019 were randomly divided into control group (N = 30) and observation group (N = 30). The patients in control group received routine rehabilitation therapy and the observation group received routine rehabilitation therapy combined with vocalization training. All patients were treated for 4 weeks. Standardized Swallowing Assessment (SSA) was used to evaluate the swallowing function of 2 groups before and after 4⁃week training. Maximum phonation time (MPT) and maximum phonation decibel were used to evaluate the laryngeal function and vocal cord vibration. Drooling part of Unified Parkinson's Disease Rating Scale Ⅱ (UPDRS Ⅱ), Drooling Severity and Frequency Scale (DSFS) were used to evaluate drooling severity (DSFS⁃S) and frequency (DSFS⁃F). All the tests were carried out before and after 4⁃week training. Results After 4⁃week training, SSA score (P = 0.000) was lower than the score before training in both groups. MPT (P = 0.000) and maximum phonation decibel (P = 0.000) were significantly increased, moreover, drooling part of UPDRS Ⅱ score (P = 0.000), DSFS⁃S score (P = 0.000) and DSFS⁃F score (P = 0.000) were significantly decreased after 4⁃week training in both groups. Compared with control group, MPT (P = 0.010) and maximum phonation decibel (P = 0.000) were increased, and SSA score (P = 0.044), drooling part of UPDRS Ⅱ score (P = 0.020), DSFS⁃S score (P = 0.044) and DSFS⁃F score (P = 0.049) were decreased in the observation group. Conclusions Vocalization training could mitigate drooling severity and frequency of the patients with PD by improving the swallowing function. DOI：10.3969/j.issn.1672⁃6731.2019.11.014