Can We Rely Solely on the International Prostate Symptoms Score to Investigate Storage Symptoms in Men with Lower Urinary Tract Symptoms Associated with Benign Prostatic Enlargement? Findings from a Cross-sectional Study

Background: Discrepancies exist between patient-reported storage phase symptoms severity and International Prostate Symptom Score (IPSS) scores. Objective: To investigate whether the Overactive Bladder questionnaire (OABq) can detect further storage phase lower urinary tract symptoms (LUTS) among patients complaining solely of voiding LUTS based on the IPSS questionnaire, and to address the real-life impact of voiding LUTS towards patients’ quality of life (QoL). Design, setting, and participants: Data from 233 consecutive men seeking medical help for LUTS/benign prostate enlargement for the first time were analysed. All patients completed both the OABq and the IPSS questionnaire. In order to investigate patients with predominantly voiding phase symptoms, men with storage phase symptoms at IPSS were eventually excluded from the analysis. Patients with an OABq score of ≥40 were considered as those having moderate-to-severe storage LUTS. Outcome measurements and statistical analysis: Descriptive statistics and linear regression models tested the associations between OABq scores, IPSS, and IPSS-QoL. Results and limitations: OABq scores were higher in men with severe voiding symptoms than in men with mild voiding symptoms (p < 0.001). More than half of patients with predominant voiding symptoms, according to the IPSS questionnaire, depicted a pathologic OABq score. A higher rate of pathologic OABq scores was found in men with moderate/severe voiding symptoms than in those with mild scores (67.4% vs 49.6%, p < 0.001). At multivariable analysis, younger age (beta –0.1, p < 0.01), IPSS voiding subscore (beta 0.3, p < 0.001), and OABq score ≥40 (beta 1.1, p < 0.001) emerged as independent predictors of IPSS-QoL after accounting for prostate volume and flow max. Conclusions: The OABq can detect the presence of further storage phase LUTS in patients presenting solely with voiding LUTS and IPSS suggestive of voiding phase symptoms. In addition, the OABq was associated with worse patient QoL regardless of the severity of voiding symptoms. Patient summary: The Overactive Bladder questionnaire (OABq) is able to detect the presence of additional storage lower urinary tract symptoms (LUTS) in patients presenting solely with voiding LUTS according to the IPSS questionnaire. Moreover, the OABq is associated with worse quality of life in these patients regardless of the severity of voiding symptoms.