Lack of correlation of the American Urological Association Symptom 7 Index with urodynamic bladder outlet obstruction

Abstract

The objective of this study is to assess whether subjective information from the American Urological Association (AUA) Symptom 7 Index correlates with or predicts objective urodynamic parameters of bladder outlet obstruction. Seventy-five men, mean age 67 years (range 42-85 years), were referred for evaluation of "prostatism." Evaluation consisted of the AUA Symptom 7 Index, noninvasive uroflow, post-void residual (PVR) urine measurement, and pressure-flow analysis. Men were categorized as "obstructed," "equivocal," or "unobstructed" according to pressure-flow nomogram of Abrams and Griffiths. The total AUA 7 score, and all individual components, were compared with all invasive urodynamic parameters, and to the pressure-flow categories of obstructed, equivocal, or unobstructed. The AUA index severity categories (mild 0-7, moderate 8-19, and severe > or = 20) were compared to the urodynamic pressure flow categories. Thirty-three men had severe symptoms, and 42 had moderate or mild symptoms. Forty men were urodynamically obstructed, and 35 men were equivocal or unobstructed. There was no correlation of any AUA index parameter (total symptom score, obstructive or irritative score component, or any individual question) with any noninvasive urodynamic parameter. The sensitivity and specificity of the AUA index for urodynamic obstruction was 42.5% and 54.3% respectively. Multivariable logistic regression analysis was used to determine whether clinical data easily obtained in the office setting (age, PVR, noninvasive maximum and average flow rates) could predict urodynamic obstruction when combined with any component of the AUA index. Only age was found to be a significant predictor of obstruction status (P = 0.026). Subjective information from the AUA Symptom 7 Index does not correlate with objective data assessing bladder outlet obstruction. Though the AUA index is a valid clinical tool, it should not be used to gauge the presence or severity of bladder outlet obstruction.