As displayed in Fig. 6 and Additional file 1: Table S1, the pooled WMD for change of IPSS, QoL, Qmax and PVR was 4.19 (95%CI: 3.34–5.04, P < 0.0001), 0.68 (95%CI: 0.37–1.00, P < 0.0001), 1.86 (95%CI: 1.32–2.39, P < 0.0001) and 22.58 (95%CI: 9.13–36.04, P = 0.001), respectively, indicating PDE5-Is plus ABs had a significantly better effect on improving LUTS/BPH and ED without increased incidences of AEs than PDE5-Is alone. This evidence concerns the gene PDE5A and benign prostatic hyperplasia.