Combination treatment with propiverine hydrochloride plus doxazosin controlled release gastrointestinal therapeutic system formulation for overactive bladder and coexisting benign prostatic obstruction: a prospective, randomized, controlled multicenter study.

PURPOSE

We evaluated the efficacy and safety of a therapeutic modality involving propiverine combined with doxazosin in patients with overactive bladder (OAB) and benign prostatic obstruction.

MATERIALS AND METHODS

Men 50 years or older with OAB symptoms and urodynamically proven bladder outlet obstruction (Abrams-Griffith score greater than 20) were randomized (1:2) into 2 groups, namely group 1-doxazosin controlled release gastrointestinal therapeutic system formulation (4 mg once daily) only and group 2-propiverine hydrochloride (20 mg once daily) plus doxazosin controlled release gastrointestinal therapeutic system formulation for an 8-week treatment regimen.

RESULTS

A total of 211 men, including 69 in group 1 and 142 in group 2, were treated and 198 (93.8%) completed the 8 weeks of treatment. Significant improvements were noted in each group after treatment in urinary frequency, maximum flow rate, average micturition volume and International Prostate Symptom Score. Compared with group 1 improvement rates with regard to urinary frequency (23.5% vs 14.3%, p = 0.004), average micturition volume (32.3% vs 19.2%, p = 0.004), and storage (41.3% vs 32.6%, p = 0.029) and urgency (p = 0.019) International Prostate Symptom Score symptoms were more significant in group 2. Post-void residual urine was found to be significantly increased only in group 2 but this was not accompanied by urinary retention. Patient satisfaction rates were found to be significantly higher in group 2 than in group 1 (p = 0.002). Overall adverse event rates were higher in group 2 (p = 0.002), although discontinuation rates and discontinuation rates due to adverse events were not different between the 2 groups.

CONCLUSIONS

This study reveals that combination therapy consisting of alpha1-adrenoceptor antagonists with antimuscarinics represents an effective and relatively safe treatment modality in select patients with OAB coexisting with benign prostatic obstruction.