The diagnosis of benign prostatic obstruction: Development of a clinical nomogram

Abstract

Aims To develop a nomogram predicting benign prostatic obstruction (BPO). Methods We included in this study 600 men with lower urinary tract symptoms (LUTS) and benign prostatic enlargement (BPE) who underwent standardized pressure flow studies (PFS) between 1996 and 2000. Complete clinical and urodynamic data were available for all patients. Variables assessed in univariate and multivariate logistic regression models consisted of IPSS, PSA, prostate size, maximal urinary flow rate (Qmax) at free flow, residual urine (RU), and bladder wall thickness (BWT). These were used to predict significant BPO (defined as a Schäfer grade ≥ 3 in PFS). Results A preliminary multivariate model, including IPSS, Qmax at free flow and RU, suggested that only Qmax at free flow was a statistically significant predictor of BPO (P = 0.00) with a predictive accuracy (PA) of 82%. Further development of the multivariate model showed how the inclusion of BWT did not increase PA. Only transitional zone volume (TZV) proved to be an additional statistically significant predictor for BPO (P = 0.00). The combination of Qmax at free flow and TZV demonstrated a PA of 83.2% and were included in the final nomogram format. Conclusions We developed a clinical nomogram, which is both accurate and well calibrated, which can be helpful in the management of patients with LUTS and BPE. External validation is warranted to confirm our findings. Neurourol. Urodynam. 35:235–240, 2016. © 2014 Wiley Periodicals, Inc.

Development and validation of a clinical nomogram predicting bladder outlet obstruction via routine clinical parameters in men with refractory nonneurogenic lower urinary tract symptoms

“…Although our clinical nomogram targets men with refractory LUTS, its accuracy is comparable to that of the previously published nomogram or predictive model in men with treatment-naïve or common LUTS (73.5%–83.2%) 1127. The predictive model proposed by Kim et al 27 was constructed by a combination of Qmax, PVR volume, and TPV.…”

“…Nevertheless, patient age alone does not reliably influence the prediction of BOO in clinical studies. Recently, De Nunzio et al 24 reported that patient age did not differ statistically with respect to the presence of BOO in men with treatment-naïve LUTS;11 moreover, it was not a predictor of BOO in another cohort. In our cohort with refractory LUTS, the mean age of men with BOO was 66.4 years, higher than that of men without BOO (mean age 65.3 years).…”

“…Many researchers have investigated a noninvasive measurement to predict the probability of BOO in men with nonneurogenic LUTS. Several noninvasive methods with specific equipment or parameters have been reported as helpful in men with treatment-naïve or commonly nonneurogenic LUTS 67891011. From a clinical perspective, however, the prediction of the presence of BOO with noninvasive methods may be more helpful for men who exhibit LUTS/BPO refractory to several medications and subsequently consider prostatic surgery.…”

“…To overcome this problem, some noninvasive methods or parameters to predict the probability of BOO have been proposed in men with treatment-naïve or common LUTS;67891011 nevertheless, it has not been clarified whether these provide consistently good performance for clinical use in a large sample. In addition, the application of some methods with specific equipment is not always feasible in real-life practice.…”

The role of bladder wall thickness in the evaluation of detrusor underactivity: Development of a clinical nomogram

“…All patients signed an informed consent and the research protocol was developed in accordance with the Helsinki Declaration and preliminary results on the relation between BWT and BOO have been published by some of the co‐authors of our study in 1998 14 . We performed a retrospective analysis of a prospectively collected database 15–17 …”