Do the Benefits of Phosphodiesterase Type 5 Inhibitors in Male Lower Urinary Tract Symptoms Go Beyond Improved Symptoms?

Abstract

When phosphodiesterase type 5 inhibitors (PDE5Is) were first developed for clinical use, it was the observation of improved erectile function during clinical trials to evaluate their cardiovascular effects that led to investigation of their use for treating erectile dysfunction (ED). This emergence was one of the more spectacular therapeutic developments of the last couple of decades. More recent PDE5I use for lower urinary tract symptoms (LUTS) has arisen in the shadow of this, yet is potentially a big step for two reasons: PDE5Is represent a new class of action for LUTS therapy, and there might be potential for disease modification. To some extent, this application of PDE5Is has polarised opinion among clinicians between enthusiasts and sceptics. Objective markers able to pin down incontrovertible evidence of benefit show conflicting signals, and there is probably modest improvement. In a male LUTS population, the most clear-cut objective marker is the maximum flow rate, for which themodest improvement with PDE5Is might impair the credibility of therapeutic intervention in the minds of many. Nonetheless, storage symptoms are the more bothersome LUTS, and improved urgency delivers real clinical benefit, yetmay be achievedwithout a change in the flow rate or other accepted objective marker. The accumulation of evidence to support PDE5I use in LUTS has been steady, and the review by Gacci and colleagues [1] in this issue of European Urology shows how the arguments are increasingly clear regarding the beneficial response in LUTS. They summarise several key areas that are useful for developing clinical use: