Impact of cognitive dysfunction on drooling in Parkinson's disease.

Background: Parkinson's disease (PD) is commonly characterized by its motor symptoms such as resting tremor, rigidity, bradykinesia and postural instability; however, some of the most debilitating symptoms of this disease are non-motor ones such as dementia and sialorrhea (drooling). Drooling is caused by impaired swallowing and it can have a significant impact on the quality of life. However, it is still unclear whether cognitive dysfunction could exacerbate drooling. We wanted to examine if any relationship existed between drooling and dementia in PD patients. Identifying the correlation will aid physicians to screen and initiate early management of drooling in the course of PD. This can possibly lead to improvements in the quality of life in these patients.

Methods: In this retrospective study, we investigated the prevalence of drooling in 314 PD patients and further compared the difference in the prevalence of drooling in patients with dementia and without dementia. In addition, we studied the impact of gender on drooling in this patient population.

Results: Our results show that a significant correlation exists between drooling and dementia in our sample of PD patients. Furthermore, in males, the correlation between the prevalence of drooling and dementia was found to be clinically significant as compared to the female population.

Conclusion: Our findings suggest that drooling is a major concern in the course of PD and should therefore be addressed early and more aggressively in patients with dementia.