A Randomized, Open-Label, Comparative Study of Efficacy and Safety of Tolterodine Combined with Tamsulosin or Doxazosin in Patients with Benign Prostatic Hyperplasia

Background: Benign prostatic hyperplasia (BPH), a common disease in men over age 50 years, often causes bladder outlet obstruction and lower urinary tract symptoms (LUTS). Alpha blockers in combination with muscarinic receptor antagonists may have the potential to improve symptoms. This study aimed to assess the efficacy and safety of doxazosin or tamsulosin combined with tolterodine extend release (ER) in patients with BPH and LUTS. Material/Methods: In a prospective, randomized, open-label study (ChiCTR-IPR-15005763), 220 consecutive men with BPH and LUTS were allocated to receive doxazosin 4 mg and tolterodine ER 4 mg per day (doxazosin group) or tamsulosin 0.2 mg and tolterodine ER 4 mg per day (tamsulosin group). Treatment lasted 12 weeks. The primary end-point was the international prostatic symptom score (IPSS). Secondary endpoints were quality of life (QoL) and maximum flow rate (Q(max)), which were evaluated at 0, 6, and 12 weeks, and urodynamic parameters assessed at 0 and 12 weeks. Results: A total of 192 patients completed the trial. Baseline measurements showed no differences between the groups. After 6 weeks, IPSS improved in both groups and QoL was significantly better in the doxazosin group (P=0.01). After 12 weeks, Q(max), IPSS, QoL, intravesical pressure (Pves), and bladder compliance (BC) in the doxazosin group were significantly better than in the tamsulosin group (P=0.03, P< 0.001, P< 0.001, P=0.027, and P=0.044, respectively). Conclusions: Administration of alpha blockers combined with muscarinic receptor blocker for 12 weeks improved LUTS in men with BPH.