The International Prostate Symptom Score (IPSS) is the most widely used validated questionnaire to measure of lower urinary tract symptoms (LUTS) in male patients. One of its limitations is that it does not include questions regarding incontinence or pain, which often accompany LUTS, can alert the clinician to underlying neurological disease, and impact quality of life. The Urinary Distress Inventory-6 (UDI-6) includes data on these symptoms, however it is only validated in females and Danish males. We aimed to correlate corresponding questions and total scores on the UDI-6 with those on the IPSS to open the conversation on validating or incorporating part of it in additional populations of men.

All adult males presenting to a subspecialty Urogynecology and Reconstructive Pelvic Surgery and Multidisciplinary Pain clinic were administered an electronic pre-visit questionnaire which included both the UDI-6 and IPSS questionnaires. Scored variables included urinary frequency, urgency urinary incontinence (UUI), stress urinary incontinence (SUI), post-voiding incontinence (post-micturition dribble), feeling of incomplete bladder emptying, and pelvic pain. Data was tabulated and analyzed using SPSS v5 with Spearman correlation techniques.

Refer to Table 1 and Table 2 for results.

Significant positive correlations were observed between IPSS and UDI-6 measures across multiple lower urinary tract symptom domains in male patients. UDI-6 total score demonstrated a strong positive correlation with both AUA QOL score (r = 0.557, 95% CI 0.384–0.693, p < 0.001) and IPSS total score (r = 0.672, 95% CI 0.525–0.780, p < 0.001). Notably, UDI-6 total score correlated more strongly with AUA QOL than did IPSS total score itself (r = 0.557 vs r = 0.499, 95% CI 0.384–0.693 vs 0.320–0.643; both p < 0.001), suggesting that the UDI-6 may reflect patient-perceived symptom burden at least as well as the IPSS. Corresponding symptom domains also showed moderate to strong correlations, including AUA frequency with UDI frequency (r = 0.670, 95% CI 0.525–0.777, p < 0.001), AUA incomplete emptying with UDI difficulty emptying (r = 0.566, 95% CI 0.319–0.741, p < 0.001), AUA intermittency with UDI difficulty emptying (r = 0.624, 95% CI 0.393–0.781, p < 0.001), AUA weak stream with UDI difficulty emptying (r = 0.666, 95% CI 0.444–0.811, p < 0.001), and AUA push/strain with UDI difficulty emptying (r = 0.552, 95% CI 0.295–0.734, p < 0.001). IPSS total score was additionally correlated with UDI urgency urinary incontinence (r = 0.423, 95% CI 0.231–0.583, p < 0.001) and pelvic pain (r = 0.419, 95% CI 0.226–0.580, p < 0.001), and more weakly with UDI stress urinary incontinence (r = 0.220, 95% CI 0.014–0.409, p = 0.035), while correlation with post-void dribbling/leakage was not statistically significant (r = 0.175, 95% CI -0.034 to 0.369, p = 0.097).

UDI-6 showed significant correlation with IPSS total and individual symptom measures in male patients, supporting its potential role as a clinically useful instrument for assessing lower urinary tract symptoms in this population. Notably, UDI-6 total score correlated more strongly with AUA QOL than did IPSS total score, suggesting that the UDI-6 may capture patient-perceived symptom burden at least as well as existing symptom-based instruments. By capturing both traditional LUTS domains and additional symptom features such as urinary incontinence, the UDI-6 or its component questions present the opportunity for expanding assessment of male urinary symptom burden. Validation in additional male cohorts is warranted to confirm its performance and define its role alongside established instruments such as the IPSS.

Utomo E, Korfage IJ, Wildhagen MF, Steensma AB, Bangma CH, Blok BF. Validation of the Urogenital Distress Inventory (UDI-6) and Incontinence Impact Questionnaire (IIQ-7) in a Dutch population. Neurourol Urodyn. 2015;34(1):24-31. doi:10.1002/nau.22496
Barry MJ, Fowler FJ Jr, O'Leary MP, et al. The American Urological Association symptom index for benign prostatic hyperplasia. The Measurement Committee of the American Urological Association. J Urol. 1992;148(5):1549-1564. doi:10.1016/s0022-5347(17)36966-5