Urinary dysfunction in Parkinson's disease.

Urinary symptoms are very common in Parkinson's disease (PD). They are primarily irritative (frequency, urgency, urge incontinence) and correlate with the urodynamic finding of involuntary detrusor contractions at early stages of bladder filling (detrusor hyperreflexia). Obstructive symptoms (hesitancy, weak urinary stream) may be seen in a smaller number of patients by themselves or combined with irritative symptoms. They may be secondary to anticholinergics, obstructive uropathy, or point to the presence of multiple system atrophy. Dysfunction of the striated urethral sphincter and pelvic musculature can be seen in variable numbers in PD, with the main abnormality that of delayed relaxation at the time of initiation of voluntary voiding.