Hvidtfeldt Ulla Arthur, Erdmann Friederike, Urhøj Stine Kjær, Brandt Jørgen, Geels Camilla, Ketzel Mattias, Frohn Lise M, Christensen Jesper Heile, Sørensen Mette, Raaschou-Nielsen Ole
Danish Cancer Society Research Center, Strandboulevarden 49, Copenhagen DK-2100, Denmark.
German Childhood Cancer Registry, Institute for Medical Biostatistics, Epidemiology and Informatics (IMBEI), Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 69, Mainz 55131, Germany.
EClinicalMedicine. 2020 Oct 5;28:100569. doi: 10.1016/j.eclinm.2020.100569. eCollection 2020 Nov.
The etiology of childhood cancer is poorly understood. The role of environmental factors, including air pollution (AP) exposure, has been addressed previously, but results so far have been inconclusive. In this study, we investigate the association between long-term AP exposures in relation to childhood cancer subtypes in Denmark (1981-2013).
We conducted a nationwide register-based case-control study. We identified 7745 incident cases of childhood cancers (<20 years) in the Danish Cancer Registry. Four randomly selected (cancer-free) controls were matched to each case according to sex and date of birth. We modelled concentrations of nitrogen dioxide (NO), fine particles (PM), and black carbon (BC) at all addresses and calculated a time-weighted average from birth to index-date with a state-of-the-art multiscale AP modelling system. We analyzed the risk of childhood cancer in conditional logistic regression models adjusted for socio-demographic variables obtained from registers at the individual and neighborhood level.
The main analyses included 5045 cases and 18,179 controls. For all cancers combined, we observed odds ratios (ORs) and 95% confidence intervals (95% CI) of 0·97 (0·94, 1·01) per 10 µg/m NO, 0·89 (0·82, 0·98) per 5 µg/m PM, and 0·94 (0·88, 1·01) per 1 µg/m BC, respectively. Most notably, we observed a higher risk of Non-Hodgkin Lymphoma (NHL) with higher childhood AP exposure with ORs and 95% CIs of 1·21 (0·94, 1·55) per 10 µg/m NO, 2·11 (1·10, 4·01) per 5 µg/m PM, and 1·68 (1·06, 2·66) per 1 µg/m BC, respectively. We observed indications of increased risks for other types of childhood cancer, however, with very wide CIs including 1.
The findings of this nation-wide study propose a role of AP in the development of childhood NHL, but more large-scale studies are needed.
NordForsk Project #75007.
儿童癌症的病因尚不清楚。此前已探讨过环境因素的作用，包括接触空气污染（AP），但迄今为止结果尚无定论。在本研究中，我们调查了丹麦（1981 - 2013年）长期接触AP与儿童癌症亚型之间的关联。
我们进行了一项基于全国登记处的病例对照研究。我们在丹麦癌症登记处确定了7745例儿童癌症（<20岁）新发病例。根据性别和出生日期，为每个病例随机选取4名（无癌症）对照。我们对所有地址的二氧化氮（NO）、细颗粒物（PM）和黑碳（BC）浓度进行建模，并使用先进的多尺度AP建模系统计算从出生到索引日期的时间加权平均值。我们在条件逻辑回归模型中分析了儿童癌症风险，并根据从个人和社区层面的登记处获得的社会人口统计学变量进行了调整。
主要分析纳入了5045例病例和18179名对照。对于所有癌症合并分析，我们观察到每10μg/m³ NO的比值比（OR）和95%置信区间（95%CI）为0.97（0.94，1.01），每5μg/m³ PM为0.89（0.82，0.98），每1μg/m³ BC为0.94（0.88，1.01）。最值得注意的是，我们观察到儿童期接触AP水平较高时，非霍奇金淋巴瘤（NHL）风险更高，每10μg/m³ NO的OR和95%CI为1.21（0.94，1.55），每5μg/m³ PM为2.11（1.10，4.01），每1μg/m³ BC为1.68（1.06，2.66）。我们观察到其他类型儿童癌症风险增加的迹象，然而，置信区间非常宽，包括1。
这项全国性研究的结果表明AP在儿童NHL的发生发展中起作用，但还需要更多大规模研究。
北欧研究理事会项目#75007。
