(a) Mean score on each domain of the PDQ-39 at the baseline in PD patients from the entire cohort with vs. without drooling; p < 0.0001 for all analysis except for “emotional well-being” (p = 0.001), “stigmatization” (p = 0.129), and “pain and discomfort” (p = 0.063). (b) Mean score on each domain of the EUROHIS-QOL8 at the baseline in PD patients from the entire cohort with vs. without drooling; “quality of life,” p = 0.005; “health status,” p = 0.178; “energy,” p = 0.183; “autonomy for ADL,” p = 0.011; “self-esteem,” p = 0.033; “social relationships,” p = 0.032; “economic capacity,” p = 0.020; “habitat,” p = 0.046. EUROHIS-QOL8, EUROHIS-QOL 8-item index; PD, Parkinson's disease; PDQ-39, 39-item Parkinson's disease quality of life questionnaire.