Finasteride May Be Helpful for Benign Prostatic Hypertrophy

Laurie Barclay, MD

October 08, 2010

October 8, 2010 — Long-term use of finasteride may reduce urinary tract symptoms and disease progression of benign prostatic hyperplasia (BPH) to a greater extent than placebo and some other drugs, according to the results of a systematic review reported online October 6 in the Cochrane Database of Systematic Reviews.

"We needed to determine the effectiveness and harms of finasteride when used on its own or in combination with other therapies, and to compare this with similar drugs," lead author James Tacklind, from the Veterans Affairs Medical Center in Minneapolis, Minnesota, said in a news release. "Finasteride seems to be more effective in men with large prostates who use the drugs for at least 1 year, compared to those with small prostates."

The study goal was to compare the clinical effectiveness and harms of finasteride vs placebo and active controls in the treatment of lower urinary tract symptoms.

"[BPH], a non-malignant enlargement of the prostate in aging men, can cause bothersome urinary symptoms (intermittency, weak stream, straining, urgency, frequency, incomplete emptying)," the review authors write. "Finasteride, a five-alpha reductase inhibitor (5ARI), blocks the conversion of testosterone to dihydrotestosterone, reduces prostate size, and is commonly used to treat symptoms associated with BPH."

Inclusion criteria were randomized controlled trials in the English language with placebo and/or active groups and with a duration of 6 months or more. To identify studies meeting selection criteria, the reviewers searched CDSR (Cochrane Database of Systematic Reviews), DARE (Database of Abstracts of Reviews of Effects), HTA (Heath Technology Assessments), CENTRAL (Cochrane Central Register of Controlled Trials, which includes EMBASE and MEDLINE), LILACS (Latin American and Caribbean Center on Health Sciences Information), and Google Scholar. They also hand searched systematic reviews, references, and clinical practice guidelines.

Dr. Tacklind extracted data regarding patient characteristics, outcomes, and adverse effects. The main study endpoint was change in the American Urological Association symptom index (AUA)/International Prostate Symptom Score (IPSS) or other validated urinary symptom scale score, with a clinically meaningful change defined as 4 points. Outcomes were also classified by short-term (≤1 year) or long-term (>1 year) trial duration.

In long-term trials, finasteride was associated with consistently improved urinary symptom scores compared with placebo, as well as with significant reduction in risk for BPH progression, defined as acute urinary retention, risk for surgical intervention, and/or a 4-point or more increase in AUA/IPSS.

Compared with alpha-blocker monotherapy, finasteride was as effective as tamsulosin but less effective than either doxazosin or terazosin in improving peak urine flow and nocturia. Risk for surgical intervention was lower with finasteride vs doxazosin, but not vs terazosin. Risk for acute urinary retention was similar for finasteride and doxazosin.

For finasteride vs placebo, risk was increased for ejaculation disorder, impotence, and lowered libido. Compared with doxazosin or terazosin, finasteride had a lower risk for asthenia, dizziness, and postural hypotension.

"Finasteride improves long-term urinary symptoms versus placebo, but is less effective than doxazosin," the study authors write. "Long-term combination therapy with alpha blockers (doxazosin, terazosin) improves symptoms significantly better than finasteride monotherapy. Finasteride + doxazosin improves symptoms equally — and clinically — to doxazosin alone. In comparison to doxazosin, finasteride + doxazosin appears to improve urinary symptoms only in men with medium (25 to < 40 mL) or large prostates (≥ 40 mL), but not in men with small prostates (25 mL)."

The authors have disclosed no relevant financial relationships.

Cochrane Database Syst Rev. Published online October 6, 2010.