In 2015, XH Wang et al. [19] conducted an meta-analysis to summarize the comparative effect and safety of monotherapy and combination therapy of PDE5-Is and ABs for LUTS/BPH, in which they suggested that PDE5-Is used alone was effective except for Post-Void Residual (PVR) than ABs and was more effective than ABs on increase of International Index Of Erectile Function (IIEF) score while combination therapy had the best effect. This evidence concerns the gene PDE5A and benign prostatic hyperplasia.