Innovation and Policy Center for Population Health and Sustainable Environment, College of Public Health, 33561National Taiwan University, Taipei, Taiwan.
Institute of Environmental and Occupational Health Science, College of Public Health, 33561National Taiwan University, Taipei, Taiwan.
Cancer Control. 2021 Jan-Dec;28:10732748211041232. doi: 10.1177/10732748211041232.
The roles of ambient fine particulate matter (PM) in the prevention of colorectal cancer (CRC) have been scarcely highlighted as there is short of empirical evidence regarding the influences of PM on multistep carcinogenic processes of CRC. A retrospective cohort design with multistate outcomes was envisaged by linking monthly average PM concentrations at 22 city/county level with large-scale cohorts of cancer-screened population to study the influences of PM on short-term inflammatory process and multistep carcinogenic processes of CRC. Our study included a nationwide CRC screening cohort of 4,628,995 aged 50-69 years who attended first screen between 2004 and 2009 and continued periodical screens until 2016. We aimed to illustrate the carcinogenesis of PM related to CRC by applying both hierarchical logistical and multistate Markov regression models to estimate the effects of air pollution on fecal immunochemical test (FIT) positive (a proxy of inflammatory marker) and pre-clinical and clinical states of CRC in the nationwide cohort. We found a significant association of high PM exposure and FIT-positive by an increased risk of 11% [95% confidence interval (CI), 10-12]. PM enhanced the risk of being preclinical state by 14% (95% CI, 10-18) and that of subsequent progression from pre-clinical to clinical state by 21% (95% CI, 14-28). Furthermore, the elevated risks for CRC carcinogenesis were significantly higher for people living in high PM pollution areas in terms of yearly averages and the number days above 35 µg/m than those living in low PM pollution areas. We concluded that both short-term and long-term PM exposure were associated with multistep progression of CRC, which were useful to design precision primary and secondary prevention strategies of CRC for people who are exposed to high PM pollution.
大气细颗粒物（PM）在预防结直肠癌（CRC）中的作用尚未得到充分强调，因为缺乏有关 PM 对 CRC 多步致癌过程影响的经验证据。通过将 22 个城市/县的每月平均 PM 浓度与癌症筛查人群的大规模队列相联系，我们设想了一个具有多状态结局的回顾性队列设计，以研究 PM 对 CRC 的短期炎症过程和多步致癌过程的影响。我们的研究包括一个全国性的 CRC 筛查队列，该队列由 4628995 名年龄在 50-69 岁之间的人群组成，他们在 2004 年至 2009 年间参加了首次筛查，并在 2016 年之前定期进行筛查。我们旨在通过应用分层逻辑回归和多状态马尔可夫回归模型来阐明与 CRC 相关的 PM 致癌作用，来估计空气污染对全国性队列中粪便免疫化学试验（FIT）阳性（炎症标志物的代表）和 CRC 临床前和临床状态的影响。我们发现，高 PM 暴露与 FIT 阳性显著相关，风险增加 11%（95%置信区间，10-12%）。PM 使进入临床前状态的风险增加了 14%（95%置信区间，10-18%），随后从临床前状态进展到临床状态的风险增加了 21%（95%置信区间，14-28%）。此外，与生活在 PM 污染较低地区的人相比，生活在 PM 污染较高地区的人，CRC 发生的风险显著更高。我们得出结论，短期和长期 PM 暴露与 CRC 的多步进展相关，这对于为暴露于高 PM 污染的人群设计 CRC 的精准一级和二级预防策略是有用的。
