Managing benign prostatic hyperplasia CMAJ 1997;156:979 In response to: J. Barkin The trial involving veterans, published while our article was in press, concluded that terazosin was significantly more effective than placebo, whereas finasteride was not. However, it turned out that the patients enrolled in this study had a mean prostate size identical to that in a normal population of men.[2] A meta-analysis (incorporating the results of our Canadian study) subsequently confirmed that only patients with enlarged prostates had a response significantly better than those taking a placebo.[3] It is obvious now, but not when we designed our study in 1991, that a drug whose action is to shrink the prostate only works in men with large prostates. Many of us, including Dr. Barkin, are concerned about the unacceptable failure rate of drug therapy, particularly after several years. In a long-term study of terazosin,[4] twice as many patients with small prostates (32%) as with larger prostates (16%) were still available for study after 4 years. By contrast, more than 90% of patients taking finasteride who entered open-label trials (and who presumably had a favourable response secondary to shrinkage and stabilization of their prostates) were still taking the drug and were available for study 5 years later.[5] These new and important findings allow busy clinicians such as Barkin a less confusing and more efficient, durable and evidence-based approach to the treatment of his patients who do not choose watchful waiting, who have an indication for drug therapy or who are reluctant to undergo surgery. Most men with symptoms but with normal-size prostates (50% or more of Barkin's patients) can be expected to have a favourable and durable response to alpha-blocking agents. Both alpha-blocking agents and finasteride can achieve similar results in men with larger prostates. With finasteride, we can expect the response to be durable over the long term. Barkin was also concerned about the confusing finding of the study involving veterans that the PSA level decreased in the terazosin group, but not in the finasteride group.[1] In fact, the result was precisely the opposite. This error had passed through proofreaders, editors and multiple authors. One must question everything one reads. Even the New England Journal of Medicine can make a mistake. J. Curtis Nickel, MD Professor of Urology Queen's University Kingston, Ont. References Lepor H, Williford WO, Barry MJ, Brawer MK, Dixon CM, Gormley G, et al. The efficacy of terazosin, finasteride, or both in benign prostatic hyperplasia. N Engl J Med 1996;335:533-9. Girman CJ, Jacobsen SJ, Guess HA, et al. Natural history of prostatism: relationship among symptoms, prostate volume and peak urinary flow rate. J Urol 1996;153:1510-5. Boyle P, Gould AL, Roehrborn CG. Prostate volume predicts outcome of treatment of benign prostatic hyperplasia with finasteride: meta-analysis of randomized clinical trials. Urology 1996;48:398-405. Brawer M. The impact on response to long-term terazosin treatment in patients with symptomatic benign prostate hyperplasia (BPH). Eur Urol 1996;30(suppl 2):152. Moore E, Bracken B, Bremner W, et al. Proscar: five-year experience. Eur Urol 1995;28:304-9. Send a letter to the editor responding to this letter Envoyez une lettre à la rédaction au sujet de cette lettre | CMAJ April 1, 1997 (vol 156, no 7) / JAMC le 1er avril 1997 (vol 156, no 7) |