Prevalence and clinical correlates of drooling in Parkinson disease: a study on 518 Chinese patients.

BACKGROUND: The prevalence and clinical correlates of drooling in Chinese patients with Parkinson disease (PD) are unknown. METHODS: A cross-sectional analysis of 518 Chinese patients with PD was conducted. Assessments included Unified PD Rating Scale (UPDRS), Non-Motor Symptoms Scale (NMSS), Hamilton Depression Scale (HAMD), Hamilton Anxiety Scale (HAMA), PD Questionnaire-39 (PDQ-39), Frontal assessment battery (FAB) and Montreal Cognitive Assessment (MoCA). RESULTS: Two hundred and seventy-three PD patients (52.7%) reported drooling (droolers). Drooling occurred more frequently in the late-onset PD patients than the early-onset PD patients (p < 0.05). Droolers had higher levodopa equivalent daily doses, higher incidences of dysarthria, dysphagia and fluctuation, higher scores for the UPDRS part III, NMSS, HAMD and HAMA, and higher scores for the mobility, activities of daily life, stigma and communication subdomains of the PDQ-39 than the non-droolers (p < 0.05). The percentage of benzhexol use in the non-droolers was significantly higher than the droolers (p < 0.05). The FAB and MoCA scores between the droolers and non-droolers were not different. The binary logistic regression analysis indicated that dysarthria, dysphagia, benzhexol use, and a lower score for the naming domain of the MoCA were associated with drooling. CONCLUSIONS: Drooling is a relatively common disabling symptom in Chinese PD patients. Patients with dysarthria, dysphagia and naming disorder are likely to experience drooling. Drooling is not correlated with disease duration and motor severity of PD.