Parkinson's Disease (PD) is a common, progressive neurodegenerative disease, affecting approximately 1% of the population aged 60 years and over [1]. The associated morbidity and mortality are increasing at a faster rate than for any other neurological disorder [2]. Lower urinary tract symptoms (LUTS) are reported in up to 85% of patients and can significantly impair quality of life [3]. There are few studies that utilise the Montreal Cognitive Assessment (MoCA) to score cognitive performance and compare this against motor symptoms and LUTS severity. Moreover, a paucity of data exists on how these relationships differ between non-drug-naïve and drug-naïve PD (de novo PD).

To assess the baseline LUTS, motor, and cognitive function and correlations using validated clinical questionnaires in patients diagnosed with PD.

An observational, cross-sectional study. Data were prospectively collected from patients diagnosed with PD attending a specialist movement disorders clinic using fully validated [3], detailed questionnaires and scales routinely employed in clinical practice (ICIQ-MLUTS; ICIQ-FLUTS; Unified PD Rating Scale – Motor Examination (UPDRS-ME); modified Hoehn and Yahr; MoCA). Statistical analyses were performed using Stata/MP 17.

Data from 18 patients were collected (15 male and 3 female subjects; median age 69 years; median disease duration 4 years; median modified Hoehn and Yahr stage 2.5; median MoCA score 24). Urinary incontinence symptoms scores were significantly correlated with worse quality of life (QoL) scores due to LUTS (r = 0.73, p < 0.001), with total urinary symptoms scores (r = 0.82, p < 0.001), and negatively correlated with MoCA scores (r = -0.52, p = 0.046). No correlation was found between urinary incontinence symptoms and motor symptoms severity scores (r = 0.09, p = 0.725). The non-drug-naïve group (n = 12, 66.7%) was found to have higher motor symptoms scores (p = 0.065), higher LUTS scores (p = 0.239), worse QoL scores due to LUTS (p = 0.244), and similar MoCA scores (p = 0.785) to the drug-naïve group (n = 6, 33.3%).

Cognitive impairment was found to be the most potent predictor of urinary incontinence symptoms.

No such link was found between urinary incontinence symptoms and motor symptoms. This suggests that cognitive function is a better predictor of functional urinary disability in PD patients than their motor symptoms severity. Non-drug-naïve PD patients were found to have higher duration of disease, more severe motor and LUTS, and similar cognitive performance compared to their drug-naïve counterparts.

Cognitive impairment in patients with PD appears to be a more potent predictor of urinary incontinence severity than motor symptoms.

de Lau and Breteler. (2006). Epidemiology of Parkinson's disease. Lancet Neurol, 5(6), 525-535. doi:10.1016/S1474-4422(06)70471-9
Pavy-Le Traon et al. (2018). Clinical Rating Scales for Urinary Symptoms in Parkinson Disease: Critique and Recommendations. Mov Disord Clin Pract, 5(5), 479-491. doi:10.1002/mdc3.12636
WHO. (2022, June 14). Launch of WHO's Parkinson disease technical brief. Retrieved April 1, 2023, from WHO: https://www.who.int/news/item/14-06-2022-launch-of-who-s-parkinson-disease-technical-brief