Voided volumes: normal values and relation to lower urinary tract symptoms in elderly men, a community-based study

To determine the normal values of voided volumes and explore the relation between bladder capacity and lower urinary tract symptoms (LUTS) in elderly men.

Data were collected from 1688 men 50 to 78 years old recruited from the population of Krimpen aan den IJssel, The Netherlands. Measurements included self-administered questionnaires (including the International Prostate Symptom Score), a 3-day frequency volume chart, transrectal ultrasonography of the prostate, uroflowmetry, and postvoid residual volume determination.

The 24-hour voided volumes were independent of age (median 1506 mL; 25th to 75th percentiles 1160 to 1950). The average volume per void and functional bladder capacity (FBC, defined as the largest single voided volume) declined with advancing age. Moreover, FBC was lower in men with a reduced maximum flow rate (less than 15 mL/s) and independent of the postvoid residual volume. Multivariate analyses showed no significant effect of prostate enlargement on the FBC. FBC was strongly related to LUTS: a low FBC coincided with higher International Prostate Symptom Scores. Multivariate logistic regression analyses revealed that the presence of moderate to severe symptoms (International Prostate Symptom Score greater than 7) was independent of prostate volume, but dependent on age, a reduced flow rate, postvoid residual volume, and FBC.

Prospective studies are needed to establish the causal relation between FBC and LUTS. Frequency volume charts are a valid, easy-to-use, noninvasive method to determine FBC as an aspect of urinary tract (dys)function in the evaluation of men with LUTS and to determine treatment options for LUTS.