Purpose: Antimuscarinic therapy for men with OAB and BOO is perceived as a potential risk for urinary retention. Using pressure flow urodynamics, we evaluated the safety of tolterodine vs placebo in men with OAB and BOO.
Materials and methods: Men (older than 40 years) with BOO and confirmed detrusor overactivity were randomized to tolterodine (2 mg twice daily in 149) or placebo (in 72) for 12 weeks. Primary end points were Qmax and pdetQmax.
Results: Median treatment differences in Qmax (-0.7 ml per second, 95% CI -1.6 to 0.4) and pdetQmax (-7 cm H2O, 95% CI -3 to 11) were comparable. Tolterodine significantly reduced the BOOI vs placebo (-9 vs 0, p < 0.02). There were significant treatment differences in volume to first detrusor contraction (+59 ml, 95% CI 19-100) and maximum cystometric capacity (+67 ml, 95% CI 35-103), favoring tolterodine over placebo (p < 0.003). Change in PVR was significantly greater among patients treated with tolterodine (+25 ml) than placebo (0 ml, p < 0.004). There were no significant between-group differences in the incidence of adverse events. Urinary retention was reported by 1 patient treated with placebo.
Conclusions: Tolterodine did not adversely affect urinary function in men with OAB and BOO. Urinary flow rate was unaltered, and there was no evidence of clinically meaningful changes in voiding pressure and PVR or urinary retention. Tolterodine was well tolerated. These results suggest that antimuscarinics can be safely administered in men with BOO.