Open-label, Intermittent Dose, Prospective Study Evaluating the Effects of Tadalafil on Lower Urinary Tract Symptoms and Erectile Function in Patients with Benign Prostatic Hyperplasia: Continuation and Durability of Effects

Effectiveness of the addition of tadalafil to tamsulosin in the treatment of acute urinary retention in patients with benign prostatic hyperplasia: A randomized clinical trial

INTRODUCTION

Acute urinary retention is one of the most significant complications of benign prostatic hyperplasia. Until now, standard treatments include catheterization and use of α-blockers. Tadalafil has been recently seen to also play a role in the treatment of urinary symptoms caused by benign prostatic hyperplasia. The aim of this study was to survey the addition of tadalafil to tamsulosin in the treatment of acute urinary retention in patients with benign prostatic hyperplasia.

MATERIALS AND METHODS

This is a randomized, double-blind placebo-controlled clinical trial. In all, 80 patients with benign prostatic hyperplasia-related acute urinary retention referred to the emergency department of the hospital were divided into two groups of 40 each and randomly assigned to receive either 0.4 mg tamsulosin plus placebo or 0.4 mg tamsulosin plus 10 mg tadalafil daily for 7 days. At the same first visit, the catheter was removed and the ability to void in 24 h and 1 week later was assessed in each group.

RESULTS

The differences in age, urine retention volume, history of drug use, lower urinary tract symptoms, and previous acute urinary retention were not significant between the two groups ( p = 0.619, 0.149, 0.501, 0.284, and 0.371, respectively). After catheter removal, 23 (57.5%) patients in the placebo group and 26 (65%) in the tadalafil group voided successfully at 24 h ( p = 0.491). After 1 week, 29 (72.5%) patients taking placebo and 26 (65%) taking tadalafil could void, yet indicating no significant difference ( p = 0.469).

CONCLUSION

Addition of tadalafil to α-blockers has no significant advantage in improving benign prostatic hyperplasia-related acute urinary retention versus tamsulosin alone.

Phosphodiesterase-5 expression and function in the lower urinary tract: a critical review

Both clinical and preclinical studies have mostly shown beneficial effects for Phosphodiesterase-5 (PDE-5) inhibitors in the treatment of lower urinary tract symptoms. Molecular studies have consistently shown abundant PDE-5 expression in bladder smooth muscle. Data concerning urethral PDE-5 expression have been surprising because striated muscle was not only positively identified, but also found to express more PDE-5 than the smooth muscle. In the prostate, highly variable results have been obtained. For PDE-5 expression, the data have ranged from extremely low to highly abundant. PDE-5 has been found in the glandular epithelium, vascular smooth muscle, endothelium, and fibromuscular stroma.

Phosphodiesterase type 5 inhibitors in the management of non-neurogenic male lower urinary tract symptoms: critical analysis of current evidence

CONTEXT

A large body of epidemiologic data suggests a causal relationship between lower urinary tract symptoms (LUTS) and erectile dysfunction (ED). Recently reported studies on phosphodiesterase type 5 inhibitors (PDE5-Is) and LUTS have further contributed to the understanding of mechanisms involved in this relationship and of potential treatment options.

OBJECTIVE

A nonsystematic descriptive review was performed to summarize the literature concerning the role of PDE5-Is in men with LUTS, particularly looking at data derived from clinical trials in relation to the different PDE5-Is or their association with α-blockers.

EVIDENCE ACQUISITION

A comprehensive electronic search was conducted in October 2010 using the Medline database to identify all publications relating to ED and BPH and treatment with sildenafil, vardenafil, tadalafil, udenafil, UK-369003, and combination therapy with alfuzosin and tamsulosin.

EVIDENCE SYNTHESIS

In studies in which either ED or LUTS was the entry criterion, sildenafil appears to improve both erectile function and LUTS in subjects with ED. Placebo-controlled trials of tadalafil and vardenafil showed improvement of LUTS secondary to benign prostatic hyperplasia (BPH), but none of the studies showed a significant effect on urodynamic measures. Exploratory studies with UK-369003 showed improvements in LUTS and ED. Sildenafil or tadalafil associated with alfuzosin or tamsulosin showed greater benefits for the combination therapy for both LUTS and ED. The coadministration of udenafil and an α-blocker in patients with BPH and ED also appeared to improve both LUTS and ED severity.

CONCLUSIONS

Consistent evidence of improvements in LUTS has been shown with PDE5-Is, either alone or in combination with α-blockers. However, effects on urodynamics or objective measures of urinary flow are lacking. Further areas of research include investigation of mechanism of PDE5-Is, urodynamic studies, identification of new efficacy end points, head-to-head comparison with standard of care, potential benefit of add-on treatment, and long-term outcomes.