Changes in Overactive Bladder Symptoms after Discontinuation of a Successful Treatment with Antimuscarinic Agent: A Prospective Trial

Doo, Chin Kyung; Kim, Jin Bum; Song, Cheryn; Kim, Jin Hyun; Choi, Jong Bo; Lee, Kyu Sung; Choo, Myung Soo

Abstract

PURPOSE: To prospectively investigated the symptom changes in women with an overactive bladder (OAB) after discontinuation of 3 months of successful treatment with antimuscarinics and the pre-treatment factors that contributed to retreatment.
MATERIALS AND METHODS
Sixty-eight women (mean age 51.4 years) with improvement in the symptoms of OAB after 4 weeks of treatment with propiverine hydrochloride (20mg/day) were prospectively enrolled in a protocol consisting of 8 further weeks of medication and a 4-week period of discontinuation. The frequency-volume charts were assessed before treatment, after the 12 weeks of therapy, and 4 weeks the end of the therapy. Changes in the frequencies, nocturia, urgency scores and urge incontinence at 12 and 16 weeks were evaluated.
RESULTS
All of the OAB symptoms 4 weeks after discontinuation of medication remained improved compared to those initially recorded, but then deteriorated during further medication. At the baseline, and 12 and 16 weeks, the mean frequencies, nocturia and urgency scores per day were 11.2, 7.3 and 8.3, 1.6, 0.4 and 0.8, and 1.7, 0.6 and 1.2, respectively. The retreatment rate was 35.3%. Patients in the retreatment group were older (58.8 vs. 47.3 years, p<0.001) and had higher initial urgency scores (1.9 vs. 1.6, p=0.034). In an urodynamic study of 23 patients, those without detrusor overactivity (DO) maintained a significantly improved frequency after cessation of mediation, whereas those with DO (60.9%) did not. The retreatment rate was higher in patients with DO, but the difference was not significant.
CONCLUSIONS
Three months of antimuscarinic therapy for OAB may not be sufficient. Older patients, or those with severe urgency, may be more likely to return to treatment.