To evaluate the correlation of clinical and urodynamic parameters with bladder vascular resistance before and after dutasteride treatment in patients with lower urinary tract symptoms associated with benign prostatic enlargement.
METHODS:
A prospective study was conducted in 30 consecutive patients with benign prostatic enlargement who had not been satisfied with alpha-adrenergic antagonist monotherapy. Before and 24 weeks after dutasteride add-on treatment, we assessed International Prostate Symptom Score (IPSS), prostate volume (PV), urodynamic study and contrast-enhanced color Doppler ultrasonography to measure bladder vascular resistive index (RI).
RESULTS:
Twenty-four weeks after dutasteride, PV significantly decreased from 68 ± 29 to 48 ± 28 mL (P < 0.001), and there was significant improvement of IPSS (from 18.8 ± 7.7 to 13.4 ± 7.2, P < 0.001). Urgency score of IPSS was also significantly improved from 2.3 ± 1.9 to 1.4 ± 1.4 (P < 0.01) after dutasteride. On pressure-flow study, bladder outlet obstruction index (BOOI) (from 58 ± 36 to 38 ± 27, P < 0.001) and detrusor pressure at Qmax (PdetQmax) (from 73 ± 34 to 54 ± 25 cmH2 O, P < 0.001) were significantly improved. RI significantly decreased after dutasteride (from 0.548 ± 0.069 to 0.486 ± 0.064, P < 0.001). In 20 patients with persistent urgency after dutasteride, RI was less improved than in another 10 patients without urgency (change of RI 0.045 ± 0.091 vs. 0.096 ± 0.042, P < 0.05). Post-treatment BOOI and PdetQmax in patients with persistent urgency was significantly higher than in those without urgency after dutasteride (BOOI: 46 ± 28 vs. 24 ± 20, P < 0.05, PdetQmax: 62 ± 26 vs. 40 ± 17 cmH2 O, P < 0.01).
CONCLUSIONS:
Reduction of obstruction and improvement of bladder ischemia might play an important role in a beneficial impact of dutasteride on overactive bladder symptoms.