Is bladder outlet obstruction normal in elderly men without lower urinary tract symptoms?

The aim of the present study was to correlate basic voiding parameters, including uroflowmetry, symptom score, and residual urine volume with the results of pressure-flow studies applying the Abrams/Griffith nomogram, in a series of urologically asymptomatic elderly men. Twenty-nine consecutive male volunteers (median age, 66 years) without past or present urological complaints participated. Fifteen (52%) of the 29 subjectively normal men proved to have bladder outlet obstruction (BOO). Qmax <10 mL/s had a positive predictive value of 100% in diagnosing obstruction, whereas the predictive information of higher flow rates proved very modest. No significant difference existed between obstructed and unobstructed persons at any cutoff value concerning symptom score. The sensitivity as well as the positive predictive value of a residual urine volume >50 mL was zero. It is concluded that a surprisingly high prevalence of BOO in asymptomatic elderly men was demonstrated and that the correlation between pressure flow investigations and alternative diagnostic tests, i.e., flow rate, symptom score, and residual volume was weak in this group of men. It is suggested that a possible explanation for the high frequency of BOO observed in the evaluated asymptomatic men could be that the values defining obstruction have been set too low. Neurourol. Urodynam. 18:545-552, 1999.