Am J Epidemiol. 2019 Oct 1;188(10):1801-1811. doi: 10.1093/aje/kwz167.
Night-shift work involving disruption of circadian rhythms has been associated with breast cancer risk. A role in prostate cancer is also suspected, but evidence is limited. We investigated the association between night-shift work and prostate cancer incidence in the Prostate Cancer and Environment Study (PROtEuS), a population-based case-control study conducted in 2005-2012 in Montreal, Quebec, Canada. Participants were 1,904 prostate cancer cases (432 high-grade cancers) and 1,965 population controls. Detailed work schedules for each job held for at least 2 years (n = 15,724) were elicited in face-to-face interviews. Night-shift work was defined as having ever worked ≥3 hours between midnight and 5:00 am ≥3 nights/month for ≥1 year. Unconditional logistic regression was used to estimate odds ratios and 95% confidence intervals for the association between night-shift work and prostate cancer, adjusting for age, ancestry, and education. No association was found between overall prostate cancer and night-shift work metrics, including ever exposure, duration, intensity, cumulative exposure, rotating shifts, and early-morning shifts. For none of the exposure indices was there evidence of heterogeneity in odds ratios between low- and high-grade cancers. Sensitivity analyses restricting exposures to ≥7 nights/month or considering screening history yielded similar results. Our findings lend no support for a major role of night-shift work in prostate cancer development.
夜班工作扰乱昼夜节律与乳腺癌风险相关。昼夜节律紊乱与前列腺癌之间的关系也受到怀疑，但证据有限。我们在 2005 年至 2012 年期间在加拿大魁北克省蒙特利尔市进行的基于人群的病例对照研究——前列腺癌与环境研究（PROtEuS）中，调查了夜班工作与前列腺癌发病之间的关联。参与者包括 1904 例前列腺癌病例（432 例为高级别癌症）和 1965 名人群对照。在面对面访谈中详细记录了每个至少工作 2 年的工作时间表（n = 15724）。夜班工作定义为≥3 小时/晚，≥3 晚/月，≥1 年。采用非条件逻辑回归估计夜班工作与前列腺癌之间的关联的比值比和 95%置信区间，调整年龄、祖籍和教育程度。夜班工作与前列腺癌的整体发病风险之间没有关联，包括曾经暴露、持续时间、强度、累积暴露、轮班和清晨工作。对于任何暴露指数，低级别和高级别癌症之间的比值比的异质性都没有证据。将暴露限制在≥7 晚/月或考虑筛查史的敏感性分析得出了类似的结果。我们的研究结果不支持夜班工作在前列腺癌发病中起主要作用。
