Relationship between interviewer-assisted international prostate symptom score and other objective measures of bladder outlet obstruction in Southeast Nigeria: a cross-sectional study

Introduction: there are concerns that interviewerassisted administration of the International Prostate Symptom Score (IPSS) may introduce bias to the extent that values obtained may not correlate with the more objective measures of bladder outlet obstruction (BOO) in benign prostate enlargement (BPE). This study aims to determine the relationship between interviewerassisted IPSS and the more objective peak urine flow rate (Qmax) and postvoid residual urine volume (PVR) in men with lower urinary tract symptoms (LUTS) due to BPE in a low-resource setting. Methods: a cross-sectional study from July 2020 to June 2021. Using systematic random sampling, men ≥ 40 years old with LUTS attributable to uncomplicated BPE were recruited. Participants completed the English-language IPSS questionnaire with the needed assistance from the interviewer. Thereafter, the Qmax was assessed using uroflowmetry while PV and PVR were assessed using ultrasonography. Age, serum total prostate-specific antigen (tPSA), body mass index (BMI), and the highest level of formal education attained were determined. Multivariate logistic regression analysis was used to examine the relationship between these variables and IPSS. Results: in all, 170 men of mean age 63.7±9.9 years participated. The mean PV, PVR, and Qmax were 70.84±39.50 cm, 77.66±69.30 cm, and 20.25±9.70ml/s, respectively. Of these 170 participants, 134 (78.8%) attained formal education beyond the primary level. Increasing points of interviewer-assisted IPSS have a strong relationship with worsening self-perceived quality of life due to LUTS (r: 0.76; p= 0.001), but a rather weak relationship with decreasing Qmax (r:-0.40; p= 0.009) and increasing PVR (r: 0.49; p= 0.005). Higher formal education was associated with lower IPSS at presentation and was statistically significant (p = 0.004). There were no predictable relationships between IPSS and age, tPSA, PV, and BMI (p > 0.05). Conclusion: interviewer-assisted IPSS can be relied upon, but with some caution, in low-resource, low-formal education settings to give clinical information consistent with the objective measures of BOO.