Urodynamic verification of an overactive bladder is not a prerequisite for antimuscarinic treatment response.
OBJECTIVE
To investigate the place of urodynamics in the evaluation of patients with symptoms of the overactive bladder by comparing the response to antimuscarinic therapy in those with and with no urodynamically verified symptoms.


METHODS
In a prospective observational study, 356 female patients with urinary frequency (> or = 8 voids/24 h) and urgency, with or without urge incontinence, underwent cystometry. Patients were diagnosed with detrusor instability if there were spontaneous, uninhibited increases in detrusor pressure during bladder filling. All patients, regardless of urodynamic findings, were subsequently treated with oxybutynin 2.5 mg twice daily and bladder retraining. The outcome was evaluated as the change in urinary frequency and incontinence episodes after 6-8 weeks of treatment.


RESULTS
Among 352 evaluable patients, 266 (76%) had detrusor instability on cystometry and the remainder did not. There was no significant between-group difference in mean age, urinary frequency or the number of incontinence episodes at presentation. Both groups improved equally well during oxybutynin and bladder retraining therapy; after 6-8 weeks there was no significant between-group difference for the mean change from baseline in urinary frequency or incontinence episodes. Tolerability profiles were comparable for the two groups.


CONCLUSIONS
Patients with symptoms of an overactive bladder, but apparently normal urodynamic findings, respond equally well to antimuscarinic therapy as those with urodynamically verified symptoms. Such findings cast further doubt on the clinical validity of using invasive urodynamic procedures to characterize patients with irritative lower urinary tract symptoms before starting antimuscarinic therapy.
Malone-Lee
J
J
Department of Medicine, Whittington Hospital, Royal Free and University College Medical School, London, UK. James.Malone-Lee@ucl.ac.uk
Henshaw
D J E
DJ
Cummings
K
K
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008333:Mandelic Acids / Q000627:therapeutic use*; D008875:Middle Aged; D018727:Muscarinic Antagonists / Q000627:therapeutic use*; D011446:Prospective Studies; D016896:Treatment Outcome; D001745:Urinary Bladder Diseases / Q000188:drug therapy / Q000503:physiopathology*; D014549:Urinary Incontinence / Q000188:drug therapy / Q000503:physiopathology*; D014554:Urination / Q000187:drug effects; D014563:Urodynamics / Q000187:drug effects*
D008333:Mandelic Acids; D018727:Muscarinic Antagonists; C005419:oxybutynin