A review of the clinical efficacy and safety of 5alpha-reductase inhibitors for the enlarged prostate.
BACKGROUND
Enlargement of the prostate is common among aging men, with an incidence of 90% by the age of 85 years. It is a progressive condition, with growth in prostate size accompanied by lower urinary tract symptoms that can result in long-term complications (eg, acute urinary retention [AUR], need for enlarged prostate-related surgery). Current pharmacologic treatment options include alpha-blockers (alfuzosin, doxazosin, tamsulosin, and terazosin) and 5alpha-reductase inhibitors (5ARIs) (finasteride and dutasteride).


OBJECTIVE
This article reviews the natural history of enlarged prostate and the data supporting management of this condition with alpha-blocker and 5ARI therapy, either as monotherapy or combination therapy, for symptomatic relief and a reduction in long-term disease progression.


METHODS
Pertinent English-language articles were identified through a search of MEDLINE (1966-week 2, May 2006) using such search terms as 5alpha-reductase inhibitor, alpha-blocker, benign prostatic hyperplasia, dutasteride, efficacy, enlarged prostate, finasteride, and safety.


RESULTS
Clinical trials of alpha-blockers in men with enlarged prostate have reported improvements in total symptom scores of 10% to 20% compared with placebo; however, these agents were not shown to reduce the risk of long-term complications or disease progression. Studies of the 5ARIs have reported significant reductions compared with placebo in the relative risk for AUR and enlarged prostate-related surgery, slowing of disease progression, and relief of symptoms. In studies of dutasteride, improvements in symptom scores were greater after 4 years of therapy compared with 2 years (-6.4 vs -4.3 points, respectively) and flow rates were better (2.6 vs 2.3 mL/sec). Six-year data for finasteride showed maintenance of the decreased risk for AUR and enlarged prostate-related surgery. Use of combination therapy with an alpha-blocker and a 5ARI may be of benefit in patients who require immediate relief of symptoms, with discontinuation of the alpha-blocker after several months of therapy. 5ARIs were generally well tolerated, with sexual dysfunction the most frequently reported adverse effect, although in only a small proportion of men (1%-8%).


CONCLUSIONS
The use of 5ARI therapy is a rational approach to symptom management and prevention of long-term negative outcomes in men with enlarged prostates.V 3.
Naslund
Michael J
MJ
University of Maryland School of Medicine, Baltimore, Maryland 21201, USA. mnaslund@smail.umaryland.edu
Miner
Martin
M
D000317:Adrenergic alpha-Antagonists / Q000009:adverse effects / Q000627:therapeutic use*; D000368:Aged; D000369:Aged, 80 and over; D001378:Azasteroids / Q000009:adverse effects / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D000068538:Dutasteride; D004791:Enzyme Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D018120:Finasteride / Q000009:adverse effects / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D011470:Prostatic Hyperplasia / Q000150:complications / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D016032:Randomized Controlled Trials as Topic
D000317:Adrenergic alpha-Antagonists; D001378:Azasteroids; D004791:Enzyme Inhibitors; D018120:Finasteride; D000068538:Dutasteride