Parkinson’s disease (PD) is an age-related neurodegenerative disorder characterized by motor symptoms, such as tremor, slowness (bradykinesia) and postural instability. Global prevalence has doubled in the past 25 years, with 8.5 million people affected worldwide in 2019(1). PD is also associated with other 'non motor’ symptoms, including constipation and orthostatic hypotension early in the disease(2). Overt dysphagia is common later in the disease, and associated with reduced fluid intake of approximately 300 mLs per day(3). This study investigates whether fluid intake is also reduced in individuals newly diagnosed with PD.

Participants with newly diagnosed PD (within six months of diagnosis or longer if untreated) were recruited alongside household controls. Assessments included a 24-hour dietary recall, a video-recorded swallowing evaluation, and stool consistency grading using the Bristol Stool Chart.

The study enrolled 30 participants: 19 with newly diagnosed PD and 11 household controls. Fluid intake from beverages was significantly lower in the PD group compared to controls (median intake: 1124 mL vs. 1799 mL, p=0.005). Dietary fluid sources did not offset this reduction. While the PD group exhibited slightly slower drinking speeds (6.0 mL/second vs. 7.5 mL/second for controls), this difference was not statistically significant. Participants with PD also had significantly harder stools, with a mean Bristol Stool Chart score of 3.2 compared to 4.6 in controls (p=0.01).

Newly diagnosed PD is associated with reduced fluid intake from beverages, which may exacerbate constipation and orthostatic hypotension.