Ambulatory urodynamic evaluation of men with lower urinary tract symptoms treated with doxazosin.

We investigate the results of ambulatory urodynamic evaluation of men with lower urinary tract symptoms (LUTS) believed secondary to benign prostatic hyperplasia (BPH) treated with doxazosin and compare these results to conventional urodynamic study. Ten men with previously untreated LUTS underwent conventional urodynamic evaluation, which was repeated after treatment with doxazosin (4 mg daily) for 3 months. All patients continued on doxazosin and subsequently underwent ambulatory urodynamic evaluation. All men completed an International Prostate Symptom Score (I-PSS) questionnaire with a decrease in score from a mean of 20.4 initially to 8.7 after treatment with doxazosin for 3 months. The mean maximum urinary flow rate increased from 11.9 to 15.3 cc/s and the mean detrusor pressure at peak flow decreased from 99 to 82 cm H2O. The mean duration of ambulatory study was 5 h and 8 minutes (mean 6 voiding cycles). The mean ambulatory voiding pressure in the ten patients treated with doxazosin was 75 cm H2O. Ambulatory urodynamic monitoring is well tolerated by most men with LUTS. Intravesical voiding pressures remain in the obstructed range in most men treated with doxazosin despite marked improvement in urinary symptoms. Ambulatory urodynamic evaluation demonstrates that these elevated detrusor pressures are present during routine daily activities. The long-term effect of increased voiding pressures on urinary tract function is unclear.