In a Canadian study reported in JAMA Network Open, Hamilton et al found that use of 5-alpha reductase inhibitors (5-ARIs) prior to the diagnosis of prostate cancer was not associated with an increased risk of prostate cancer–specific or overall mortality.
Study Details
The study involved data from the Ontario Health Administrative Databases on men aged 65 and older who developed clinically localized prostate cancer between January 2003 and October 2017. The primary outcomes of interest were prostate cancer–specific mortality and overall mortality. Inverse probability treatment weighting (IPTW) was used to evaluate associations of 5-ARI use with mortality outcomes.
Key Findings
The study population consisted of 19,938 patients with prostate cancer, including 2,112 (10.6%) who were treated with 5-ARIs prior to their cancer diagnosis. During a median follow-up of 8.96 years (interquartile range = 6.28–12.17 years), 6,053 patients (30.4%) died, including 1,047 (5.3%) from prostate cancer.
On IPTW analysis, no significant association of 5-ARI use vs no use was observed for prostate cancer–specific mortality (hazard ratio [HR] = 1.02, 95% confidence interval [CI] = 0.83–1.25, P = .84) or overall mortality (HR = 0.98; 95% CI = 0.90–1.07, P = .77).
The investigators concluded: “In this population-based cohort study of 5-ARI use prior to [prostate cancer] diagnosis including long-term follow-up and clinicopathologic details, prediagnostic 5-ARI use was not associated with [prostate cancer–specific] or all-cause mortality. This study offers reassuring safety data for patients using 5-ARIs before [prostate cancer] diagnosis for both [benign prostatic hyperplasia] and chemopreventive reasons.”
Robert J. Hamilton, MD, MPH, of the Division of Urology, Department of Surgery, Princess Margaret Cancer Centre, Toronto, is the corresponding author of the JAMA Network Open article.
Disclosure: The study was supported by the Institute for Clinical Evaluative Sciences (ICES), which is funded by an annual grant from the Ontario Ministry of Health and the Ministry of Long-Term Care, the Canadian Cancer Society Research Institute, and others. For full disclosures of the study authors, visit jamanetwork.com.
