Twelve-month treatment of overactive bladder: efficacy and tolerability of tolterodine

Tolterodine is a bladder-selective antimuscarinic agent designed for the treatment of overactive bladder. Traditional antimuscarinic therapies are poorly tolerated due to a high incidence of anticholinergic adverse events and consequently few patients remain on long term therapy.

To evaluate the long term efficacy and tolerability of tolterodine in patients with symptoms of overactive bladder.

Twelve-month open-label extension of 4 randomised, placebo-controlled, double-blind, multinational, multicentre trials of 4 weeks' duration.

714 patients (aged 18 to 92 years) with symptoms of overactive bladder who completed the double-blind portion of the studies.

Tolterodine 2 mg twice daily for up to 12 months.

Micturition diary variables: number of micturitions per 24 hours, number of urge incontinence episodes per 24 hours, mean urine volume voided per micturition. Safety variables: adverse events, study discontinuation rate.

A total of 441 patients (62%) completed 12 months' open-label treatment with tolterodine, which significantly reduced the number of micturitions per 24 hours [mean change -2.4, 95% confidence interval (CI) -2.7 to -2.2, median change -20%, p < 0.0001] and number of urge incontinence episodes per 24 hours (mean change -1.3, 95% CI -1.6 to -1.0, median change -74%, p < 0.0001), while the mean volume voided per micturition was significantly increased (+33 ml, 95% CI +28 to +38, median change +18%; p < 0.0001). 41% of patients reported dry mouth (27% mild, 10% moderate, 3% severe). Dosage reduction to 1 mg twice daily was required in 23% of patients. 15% of patients withdrew from the study due to adverse events, with 5% having associated dry mouth.

The high percentage of patients completing 12 months' treatment indicates that tolterodine is an effective and well tolerated agent for long term treatment of overactive bladder.