Urinary retention in patients with BPH treated with finasteride or placebo over 4 years. Characterization of patients and ultimate outcomes. The PLESS Study Group

Eur Urol. 2000 May;37(5):528-36. doi: 10.1159/000020189.


Objectives: Knowledge regarding the incidence and prevalence of acute urinary retention and the ultimate outcome is very limited. The purpose of the present analysis was to document the natural history and outcomes of acute urinary retention (AUR) further specified as being either precipitated or spontaneous, and to evaluate the potential benefit of finasteride therapy.

Materials and methods: Three thousand and forty men with moderate to severe symptoms of BPH and enlarged prostate glands by digital rectal examination were enrolled into the 4-year placebo-controlled PLESS trial and were evaluated for occurrences of AUR and BPH-related surgery. Men in the study were seen every 4 months; discontinued patients were followed up 6 months after discontinuation and again at the end of the 4-year trial. Complete 4-year data on outcomes (occurrence of AUR or BPH-related surgery) was available for 92% of the enrolled subjects in each treatment group. An endpoint committee, blinded to treatment group and center, reviewed and categorized all study-related documentation relating to retention and surgery.

Results: Over the 4-year period, 99 of 1,503 placebo-treated patients (6.6%) experienced one or more episodes of AUR in comparison with 42 or 1,513 finasteride-treated patients (2.8%; p<0. 001). Approximately half of the episodes of retention were spontaneous and clearly BPH-related, while the other episodes were precipitated by another factor (PAUR). After spontaneous AUR, subsequent surgery was performed in 39 of 52 (75%) placebo-treated patients versus 8 of 20 (40%) finasteride-treated patients (p = 0. 01). BPH-related surgery was less common in men who had a prior episode of PAUR (26% in the placebo group and 14% in the finasteride group).

Conclusion: There is a continual risk of spontaneous and precipitated acute urinary retention in men with moderate to severe lower urinary tract symptoms and an enlarged prostate gland. Fewer patients who developed precipitated AUR than spontaneous AUR go on to need subsequent BPH-related surgery. Significantly fewer finasteride-than placebo-treated patients developed AUR, and among those men, fewer ultimately needed BPH-related surgery.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Finasteride / therapeutic use*
  • Humans
  • Male
  • Middle Aged
  • Prostatic Hyperplasia / complications*
  • Prostatic Hyperplasia / drug therapy*
  • Time Factors
  • Urinary Retention / drug therapy*
  • Urinary Retention / etiology*


  • Finasteride