Urinary dysfunction in early and untreated Parkinson's disease

Background: Urinary dysfunction is common in Parkinson's disease (PD); however, little is known about urinary dysfunction in early and untreated PD patients. Methods: Fifty consecutive untreated PD patients (mean age, 66.7; mean disease duration, 23.6 months; and mean Hoehn & Yahr scale, 1.9) were recruited; those with other conditions that might have influenced urinary function were excluded. Patients were evaluated using a urinary questionnaire and urodynamic studies. Results: Sixty-four per cent complained of urinary symptoms (storage, 64.0%; voiding, 28.0%). Urodynamic studies showed abnormal findings in the storage phase in 84%, with detrusor overactivity (DO) and increased bladder sensation without DO in 58.0% and 12.0% of patients, respectively. In the voiding phase, detrusor underactivity, impaired urethral relaxation such as detrusor sphincter dyssynergia, and bladder outlet obstruction were present in 50.0%, 8.0% and 16% of patients, respectively. In patients with both storage and voiding phase abnormalities, DO+detrusor underactivity was the most common finding. Few patients experienced urge incontinence and/or quality-of-life impairment owing to urinary dysfunction; none had low-compliance bladder or abnormal anal-sphincter motor unit potential. These urinary symptoms and urodynamic findings were not correlated with gender, disease severity or motor symptom type. Conclusion: Urinary dysfunction, manifested primarily as storage disorders with subclinical voiding disorders and normal anal-sphincter electromyography, occurs in early and untreated PD patients. In cases with severe voiding disorder and/or abnormal anal-sphincter electromyography, other diagnoses should be considered.