Combination of solifenacin with tamsulosin reduces prostate volume and vascularity as opposed to tamsulosin monotherapy in patients with benign prostate enlargement and overactive bladder symptoms: Results from a randomized pilot study

• Published in: International journal of urology 2018-08, Vol.25 (8), p.737-745
• Main Authors: Sakalis, Vasileios, Sfiggas, Vasileios, Vouros, Ioannis, Salpiggidis, George, Papathanasiou, Athanasios, Apostolidis, Apostolos
• Format: Article
• Language: English
• Subjects: Adenoma; Aged; Aged, 80 and over; Benign; benign prostatic hyperplasia; Bladder; combination therapy; Drug Therapy, Combination; Greece; Humans; Male; male lower urinary tract symptoms; Middle Aged; Muscarinic Antagonists - therapeutic use; Organ Size - drug effects; overactive bladder; Patients; Pilot Projects; Prospective Studies; Prostate; Prostate - drug effects; prostate volume; Prostatic Hyperplasia - drug therapy; Severity of Illness Index; Solifenacin Succinate - therapeutic use; Tamsulosin - therapeutic use; Tumors; Ultrasound; Urinary Bladder, Overactive - drug therapy; Urinary tract; Urination
• ISSN: 0919-8172; 1442-2042
• DOI: 10.1111/iju.13721

Objectives To identify the potential influence of antimuscarinics on morphometric parameters of the prostate in patients with benign prostatic enlargement and overactive bladder. Methods Non‐neurological patients with prostate volume >30 mL, predominately storage lower urinary tract symptoms, three or more urgency episodes per 24 h, maximum flow rate ≥10 mL/s and post‐void residual ≤100 mL were recruited for this study. They were randomized to receive either tamsulosin or tamsulosin + solifenacin. Patients were submitted to transrectal and transvesical ultrasonography, pressure‐flow study and prostate‐specific antigen test, and completed the International Prostate Symptom Score, bladder diary and overactive bladder questionnaire at induction and at 6 months. End‐study changes in morphometric prostate parameters (total prostate and adenoma volumes, prostate vascularity), as measured by transrectal ultrasound, were the principal outcomes. Results A reduction in total prostate volume (mean −9.5%) was noted in the combination group, as opposed to an increase in the monotherapy group (+9.2%; P < 0.001). Similar changes were reflected in adenoma volume (monotherapy +17.4% vs combination −12.5%, P = 0.001) and in prostate vascularity (monotherapy +149.3% vs combination −19.8%, P = 0.001). Both treatment regimens improved the International Prostate Symptom Score (P = 0.001); monotherapy improved the voiding subscale (P = 0.01) more, whereas combination therapy improved the storage subscale (P = 0.024). Cystometric capacity improved in the combination group (P < 0.001). Post‐void residual was increased in the combination group (+34.79%), as opposed to a decrease in the monotherapy group (−17.05%; P = 0.001). Conclusions The results of this pilot study suggest that solifenacin might affect morphometric properties of the prostate, decreasing total prostate and adenoma volume, as well as vascularity. A molecular effect of antimuscarinics on the prostate, in parallel with their expected bladder effect, warrants further investigation.