[Bladder outlet obstruction index alone is not reliable for the diagnosis of benign prostate hyperplasia]

To evaluate the clinical application value of the bladder outlet obstruction index (BOOI) in the diagnosis of BPH.

We retrospectively analyzed the urodynamic parameters and BOOI of 199 cases of BPH diagnosed from July 2016 to September 2018, which were divided into a BOO (n = 119), a suspected BOO (n = 39) and a non-BOO group (n = 41) based on the BOOI. We obtained the prostate volume (PV), IPSS, IPSS-voiding symptom score (IPSS-VS), quality of life score (QOL), maximum urinary flow rate (Qmax) and postvoid residual urine volume (PVR) from the patients, compared them among the three groups and analyzed their correlation to BOOI using Pearson's linear correlation analysis.

No statistically significant differences were observed in age (P = 0.195), PSA (P = 0.380), IPSS (P = 0.380), IPSS-VS (P = 0.380), QOL (P = 0.380), Qmax (P = 0.380) and PVR (P = 0.912) among the three groups of patients, but PV was remarkably larger in the BOO than in the suspected BOO and non-BOO groups (［58.8 ± 30.0］ vs ［49.8 ± 33.9］ and ［45.5 ± 26.0］ ml, P = 0.031). Pearson's linear correlation analysis showed that BOOI was not correlated significantly to IPSS (r = －0.020, P = 0.778), IPSS-VS (r= －0.013, P = 0.853), QOL (r = －0.107, P = 0.132), Qmax (r = －0.130, P = 0.066) or PVR (r = －0.056, P = 0.433), nor obviously to PV (|r| = 0.178<0.4) though with P = 0.012.

BOOI is not significantly correlated to PV, IPSS, IPSS-VS, QOL, Qmax or PVR, and therefore BOO cannot be diagnosed exclusively with BOOI.