Bladder dysfunction in IPD and atypical Parkinsonian disorders – pathophysiology and treatment

Lower urinary tract symptoms (LUTS) in Parkinson's disease (PD) and atypical Parkinsonian disorders (APD) are common, and animal studies have suggested that dopaminergic mechanisms may play a significant role in LUTS in PD, whereas mechanisms in APD are poorly understood.

We present data regarding the prevalence of LUTS in PD and the role of dopaminergic degeneration in the striatum. 107 patients with PD were interviewed using 2 sets of questionnaires regarding LUTS, severity of disease was assed by the modified Hoehn & Yahr rating scale, and volumes of postmicturitional urine (PMV) were measured. Scores related to troublesome LUTS correlated significant with Hoehn & Yahr stage of disease (p=0.02), but not with duration of disease or age. The most frequent symptom was nocturia, followed by frequency and urgency, patients finds urgency the most troublesome symptom. Mean PMV was 34ml. The PMV did not correlate to stage of disease, duration of disease or age or to scores on questionnaires. 6% with PD had a PMV larger then 100ml.

14 patients with Parkinson's disease were evaluated using questionnaires on bladder dysfunction, Parkinson's disease rating scales (UPDRS and Hoehn & Yahr), and single-photon emission computed tomography (SPECT) imaging of the dopamine transporter sites with I-123-FP-CIT. Patients with symptoms of bladder dysfunction have a significantly reduced uptake of [¹²³I]-FP-CIT in the striatum compared to those without symptoms. In patients with significant LUTS, the putamen-to-caudate ratio correlated significantly with bladder symptoms. As this ratio is intact throughout life in healthy individuals, bladder symptoms in the PD group may due to the specific lesion of the substantia nigra/caudate nucleus. Our studies show a high prevalence of LUTS in PD, and a clear correlation between bothersome bladder symptoms and disability related to PD; we hypothesise that a decrease in the total number of dopaminergic neurones in the striatum is associated with the presence of symptoms of urinary dysfunction and that relative degeneration of the caudate correlates to severity of symptoms and the presence of overactive detrusor. We review the literature on the differences between LUTS in PD and APD and indicate possible mechanisms and propose new studies, as well as outline possible treatment options.