OBJECTIVE: To assess the association between 5α-reductase inhibitor (5-ARI) use in men with lower urinary tract symptoms and prostate cancer risk.
DESIGN: Nationwide, population based case-control study for men diagnosed with prostate cancer in 2007-09 within the Prostate Cancer data Base Sweden 2.0.
SETTING: The National Prostate Cancer Register, National Patient Register, census, and Prescribed Drug Register in Sweden, from which we obtained data on 5-ARI use before date of prostate cancer diagnosis.
PARTICIPANTS: 26 735 cases and 133 671 matched controls; five controls per case were randomly selected from matched men in the background population. 7815 men (1499 cases and 6316 controls) had been exposed to 5-ARI. 412 men had been exposed to 5-ARI before the diagnosis of a cancer with Gleason score 8-10.
MAIN OUTCOME MEASURES: Risk of prostate cancer calculated as odds ratios and 95% confidence intervals by conditional logistic regression analyses.
RESULTS: Risk of prostate cancer overall decreased with an increasing duration of exposure; men on 5-ARI treatment for more than three years had an odds ratio of 0.72 (95% confidence interval 0.59 to 0.89; P< 0.001 for trend). The same pattern was seen for cancers with Gleason scores 2-6 and score 7 (both P< 0.001 for trend). By contrast, the risk of tumours with Gleason scores 8-10 did not decrease with increasing exposure time to 5-ARI (for 0-1 year of exposure, odds ratio 0.96 (95% confidence interval 0.83 to 1.11); for 1-2 years, 1.07 (0.88 to 1.31); for 2-3 years, 0.96 (0.72 to 1.27); for >3 years, 1.23 (0.90 to 1.68); P=0.46 for trend).
CONCLUSIONS: Men treated with 5-ARI for lower urinary tract symptoms had a decreased risk of cancer with Gleason scores 2-7, and showed no evidence of an increased risk of cancer with Gleason scores 8-10 after up to four years' treatment.
Written by:
Robinson D, Garmo H, Bill-Axelson A, Mucci L, Holmberg L, Stattin P. Are you the author?
Department of Surgery and Perioperative Sciences, Urology, and Andrology, Umeå University, 901 85 Umeå, Sweden.
Reference: BMJ. 2013 Jun 18;346:f3406.
doi: 10.1136/bmj.f3406
PubMed Abstract
PMID: 23778271
