The impact of and the factors associated with drooling in Parkinson's disease☆

We administered a 7-question survey on drooling to PD patients and age-matched controls. Each subject was assigned a drooling severity score and categorized as a “drooler” or a “non-drooler”. The age, disease duration, motor scores, quality of life (PDQ-39), and levodopa equivalent daily dosage (LEDD) were compared between PD droolers vs. PD non-droolers.

58 PD patients and 51 age-matched controls participated. In PD patients, the mean: disease duration was 10.96 years (SD 8.66) and UPDRS on motor score was 30.76 (SD 10.57). The drooling severity score was significantly different between patients vs. controls (3.41 vs. .58; p < .01). 14% of controls vs. 59% of patients were droolers (p < .01). PD droolers scored worse on the ADL subscale of the PDQ-39 (p = .031). Furthermore, PD droolers had significant difficulty speaking (7.27% vs. 0%; p < .01); eating (3.64% vs. 0%; p = .01); and socially interacting (12.73% vs. 0%; p < .01) compared to PD non-droolers. Interestingly, the hallucination component of the UPDRS Part I was significantly correlated with being a drooler (p = .016). None of the other variables have significant effect on drooling severity scores. There is a high prevalence of drooling among PD patients compared to controls.

PD droolers had worse quality of life and had more difficulty speaking, eating and socially interacting compared to PD non-droolers. Experiencing hallucinations was the only factor that correlated with being a drooler and it may be confounded by medications.