5-α-还原酶抑制剂 (5-ARIs) 被批准用于治疗良性前列腺增生 (BPH)，并被发现可将前列腺癌 (PCa) 风险降低 25%。然而，试验也表明 5-ARIs 与高级别 PCa 相关。 5-ARIs 是否会增加诊断为 PCa 的患者的死亡率尚不清楚。为了确定服用 5-ARIs 的个体与未服用者相比出现临床局部 PCa 的长期结果。这项基于人群的队列研究于 2003 年 1 月至 10 月之间进行2017 年。符合资格的参与者是加拿大安大略省 65 岁或以上的男性，他们开发了临床局部 PCa，并从安大略省健康管理数据库中提取了完整的病理学数据。数据分析发生在2017年11月至2022年11月。5-PCa诊断前的ARIs。主要结局是总体死亡率和PCa特异性死亡率。使用具有逆概率治疗权重 (IPTW) 的特定原因危害模型来检查 5-ARI 使用与死亡率结果的关联。还进行了基于诊断前 5-ARI 使用、格里森评分、合并症、5-ARI 适应症、前列腺特异性抗原模型和他汀类药物使用的敏感性分析。该队列包括 19938 名 PCa 患者。其中，2112 人（10.6%；中位 [IQR] 年龄，74 [70-79] 岁）为 5-ARI 用户，17826 人（89.4%；中位 [IQR] 年龄，71 [68-76] 岁）为非使用者。在中位 (IQR) 8.96 (6.28-12.17) 年随访期间，6053 例 (30.4%) 患者死亡，其中 1047 例 (5.3%) 死于前列腺癌。粗略分析显示，5-ARI 的使用似乎与总体死亡率和 PCa 特异性死亡率增加有关；然而，IPTW 后，5-ARI 的使用与总体死亡率（风险比，0.98；95% CI，0.90-1.07；P = .77）或 PCa 特异性死亡率（风险比，1.02；95% CI，0.83）无关。 -1.25；P = .84)。在这项以 PCa 诊断前使用 5-ARI 为基础的队列研究中，包括长期随访和临床病理学细节，诊断前使用 5-ARI 与 PCa 特异性或所有相关性无关。 -导致死亡。这项研究为因 BPH 和化学预防原因在 PCa 诊断前使用 5-ARIs 的患者提供了令人放心的安全数据。

5-alpha-reductase-inhibitors (5-ARIs) are approved for treating benign prostatic hyperplasia (BPH) and have been found to reduce prostate cancer (PCa) risk by 25%. However, trials also have shown 5-ARIs to be associated with high-grade PCa. Whether 5-ARIs increase mortality among those with a diagnosis of PCa remains unclear.To determine long-term outcomes of clinically localized PCa arising in individuals taking 5-ARIs compared with nonusers.This population-based cohort study was conducted between January 2003 and October 2017. Eligible participants were men aged 65 years or older in Ontario, Canada, who developed clinically localized PCa with complete pathological abstraction from the Ontario Health Administrative Databases. Data analysis occurred from November 2017 to November 2022.5-ARIs before PCa diagnosis.The primary outcomes were overall mortality and PCa-specific mortality. Cause-specific hazard models with inverse probability treatment weights (IPTW) were used to examine associations of 5-ARI use with mortality outcomes. Sensitivity analyses based on prediagnostic 5-ARI use, Gleason score, comorbidity, 5-ARI indication, prostate-specific antigen modeling, and statin use were also performed.The cohort included 19 938 patients with PCa. Of these, 2112 (10.6%; median [IQR] age, 74 [70-79] years) were 5-ARI users and 17 826 (89.4%; median [IQR] age, 71 [68-76] years) were nonusers. During a median (IQR) follow-up of 8.96 (6.28-12.17) years, 6053 (30.4%) died, including 1047 (5.3%) from PCa. 5-ARI use appeared to be associated with increased overall and PCa specific mortality in crude analyses; however, after IPTW, 5-ARI use was not associated with overall mortality (hazard ratio, 0.98; 95% CI, 0.90-1.07; P = .77) or PCa-specific mortality (hazard ratio, 1.02; 95% CI, 0.83-1.25; P = .84).In this population-based cohort study of 5-ARI use prior to PCa diagnosis including long-term follow-up and clinicopathologic details, prediagnostic 5-ARI use was not associated with PCa-specific or all-cause mortality. This study offers reassuring safety data for patients using 5-ARIs before PCa diagnosis for both BPH and chemopreventive reasons.