Urinary Dysfunction Worsens with Motor Progression in Parkinson’s Disease: Study
A new study published in the journal of Frontiers in Aging Neuroscience showed that as Parkinson's disease (PD) motor symptoms worsen, urinary dysfunction rises.
One typical non-motor symptom of Parkinson's disease (PD) that frequently appears early and gets worse as the disease progresses is urinary dysfunction, which severely lowers quality of life. Up to 70% of patients experience overactive bladder, which is primarily caused by detrusor overactivity as a result of impaired dopaminergic brain-bladder regulation. The suppression of the micturition reflex is compromised by degeneration of the nigrostriatal and frontal-basal ganglia.
Urinary symptoms are associated with increased disability and dopaminergic loss, and they may occur before motor indications and rise with the severity of Parkinson's disease. Evidence is still conflicting, though, especially when it comes to early phases and sex differences. Using standardized clinical instruments, this study investigates the relationship between motor severity and urine dysfunction. Using standardized clinical questionnaires to evaluate urine symptoms, this study sought to clarify this link.
A total of 223 PD patients who attended a university hospital between September 2023 and February 2024 participated within the single-center, retrospective cross-sectional research. The Overactive Bladder Symptom Score (OABSS) and International Prostate Symptom Score (IPSS), which includes the symptom (IPSS-symptom score; Q1–7) and satisfaction (IPSS-satisfaction score; Q8) scores, were used to assess urinary dysfunction. Throughout the Hoehn and Yahr (HY) phases, this study examined changes in prodromal symptoms, overall satisfaction, and urine symptoms. To evaluate early changes in urinary symptoms, patients were split into early (HY < 2) and late (HY > 2) groups.
As the HY stage advanced, there was a considerable increase in the OABSS, IPSS-symptom score, and IPSS-satisfaction score. The late group had substantially higher OABSS (p = 0.015), IPSS-symptom (p = 0.002), and IPSS-satisfaction (p < 0.001) scores than the early group. Storage symptoms had a stronger correlation with motor severity than voiding symptoms, according to subgroup analysis of the IPSS.
Overall, this study offers more proof that urinary dysfunction, particularly storage-related symptoms like OAB, gets worse as Parkinson's disease advances. To improve patients' quality of life, urinary dysfunction in Parkinson's disease must be identified and treated early. Additionally, early detection of urine dysfunction may assist differentiate Parkinson's disease (PD) from atypical parkinsonism, where voiding symptoms usually manifest earlier.
Source:
Lee, J. S., Yoo, J., Son, N.-H., Byun, H. J., & You, S. (2025). Association between motor symptom severity and urinary dysfunction in Parkinson’s disease: a retrospective study. Frontiers in Aging Neuroscience, 17(1688656),. https://doi.org/10.3389/fnagi.2025.1688656
