Solifenacin for overactive bladder in women unsuccessfully treated with immediate release oxybutynin: a pilot study

The aim of the study was to determine the efficacy, tolerability and cost comparison of solifenacin for women with an overactive bladder (OAB) who failed to respond to immediate release oxybutynin (IR). A standard 3-day bladder diary, cost of incontinence pads used over 4 weeks and a validated OAB quality-of-life questionnaire were collected at baseline, at 4 weeks and at 12 weeks of commencing solifenacin treatment. Nine women were enrolled into the study. Eight of the women completed the 12-week study and one woman withdrew. The mean number of day-time micturitions was 11.4 +/- 2.7 at baseline and 7.3 +/- 3.5 at 12 weeks of solifenacin treatment (p = 0.0002). The mean number of nocturia was 2.8 +/- 1.4 at baseline and 0.9 +/- 0.9 at 12 weeks of solifenacin treatment (p = 0.0004). The total number of incontinence episodes per day was 4.9 +/- 4.6 at baseline and 1.9 +/- 2.7 at 12 weeks of solifenacin treatment (p = 0.02). The mean micturition volumes were 160 +/- 50 ml at baseline and 280 +/- 50 ml at 12 weeks of solifenacin treatment (p = 0.002). The symptom severity domain of the OAB-questionnaire (OAB-q) showed a value of 60.8 +/- 23.0% at baseline and 32.0 +/- 25.9 % at 12 weeks of solifenacin treatment (p = 0.001). The health-related quality-of-life (HRQL) domain of the OAB-q showed a value of 45.5 +/- 28.0% at baseline and 73.3 +/- 24.8% at 12 weeks of solifenacin treatment (p = 0.0006). This study shows a significant improvement in bladder diary and validated quality-of-life parameters with solifenacin in women with urge incontinence who have previously failed to respond to or have been intolerant of oxybutynin IR.