Role of poor urethral sphincter relaxation in men with voiding dysfunction refractory to α‐blocker therapy: Clinical characteristics and predictive factors.

Objectives: This study evaluates the diagnostic value of poorly relaxed external sphincter (PRES) in men with voiding dysfunction. We analyzed clinical and video‐urodynamic characteristics to identify predictive factors of PRES in patients with lower urinary tract symptoms (LUTS) refractory to α‐1 adrenoceptor blocker (α‐blocker) therapy. Methods: This retrospective study included 3379 men with LUTS in whom the initial 1‐month α‐blocker therapy failed. Clinical parameters and video‐urodynamic results were analyzed. Patients with bladder outlet disorders including bladder neck obstruction (BNO), benign prostatic obstruction (BPO), urethral stricture (US), or PRES were categorized according to video‐urodynamic findings. Predictive factors for PRES were analyzed. Results: A total of 3379 men were included in this study. Among the patients with voiding dysfunction, 905 (43.6%) had BPO, 624 (30.0%) had BNO, 487 (23.4%) had PRES, and 62 (3.0%) had US. Patients with PRES were younger and had a higher maximum flow rate, larger bladder capacity, smaller total prostate volume (TPV) and transition zone index, and a lower rate of LUTS of urgency or urge urinary incontinence (UUI) than other groups. On multivariate analysis, only small TPV and lower urgency/UUI rate were predictive factors of PRES. A scale composed of voided volume, TPV, and urgency/UUI predicted PRES with high specificity. Conclusions: PRES was the etiology of voiding dysfunction in 23.4% of the men with LUTS refractory to α‐blocker therapy. A simple scale composed of voiding volume, TPV, and urgency/UUI was useful in predicting the presence of PRES before video‐urodynamic studies. [ABSTRACT FROM AUTHOR]