PO.PS01.12 · 人群科学
美国的野火烟雾与癌症风险：来自PLCO试验的证据
Wildfire smoke and cancer risk in the United States: Evidence from the PLCO Trial
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
背景：野火正变得日益频繁和严重，逆转了美国数十年来在减少细颗粒物（PM2.5）方面取得的进展。尽管野火烟雾（WFS）含有大量致癌物和有毒物质，但其与癌症发病率的关联仍不明确。
方法：我们在前列腺癌、肺癌、结直肠癌和卵巢癌（PLCO）癌症筛查试验中考察了WFS暴露与癌症发病率之间的关联。PLCO试验前瞻性评估了从入组（1993-2001年）至2018年的癌症发病率。WFS暴露以参与者居住地为单位按月量化，采用近地面WFS PM2.5、WFS黑碳（BC）以及卫星衍生的WFS烟羽日计数，从2006年起至首次癌症诊断或最后一次联系。基于三年空气污染暴露可影响EGFR阳性肺腺癌发生的证据，WFS暴露被建模为时变变量，采用每月之前的36个月移动平均值。采用按研究中心分层的Cox比例风险模型估算风险比（HR），并验证了比例风险假设。采用限制性立方样条评估剂量-反应关系。协变量包括年龄、性别、种族与族裔、教育程度、吸烟史、体重指数和试验组别。
结果：在91,460名具有关联WFS暴露数据的PLCO参与者中，我们于2006-2018年间识别出1,758例肺癌、800例结直肠癌、1,739例乳腺癌、242例卵巢癌、896例膀胱癌和1,696例造血系统癌症的新发病例，以及1,127例黑色素瘤。36个月移动平均值的中位数（范围）为：WFS PM2.5为0.37（0.0083-1.72）μg/m³，WFS BC为0.0083（0.00-0.21）μg/m³，每月WFS烟羽日计数为1.94（0.097-7.18）天。限制性立方样条显示WFS暴露与肺癌、结直肠癌、乳腺癌、膀胱癌和造血系统癌症风险增加存在统计学显著关联（P<0.05），且大多数分析观察到近似线性的剂量-反应关系。此外，36个月移动平均WFS PM2.5每增加1μg/m³与肺癌（HR=1.92；95% CI：1.18，3.15）、结直肠癌（2.31；1.11，4.81）、乳腺癌（2.09；1.34，3.26）、膀胱癌（3.49；1.66，7.34）和造血系统癌症（1.63；1.02，2.60）风险升高相关。未发现与卵巢癌或黑色素瘤的关联。WFS烟羽日计数的结果总体上与WFS PM2.5一致，而WFS BC暴露的关联仅见于乳腺癌和膀胱癌。
结论：WFS暴露与肺癌、结直肠癌、乳腺癌、膀胱癌和造血系统癌症的风险相关。研究结果需在其他队列中进一步验证。
查看英文原文 English abstract
Background: Wildfires are becoming more frequent and severe, reversing decades of progress in reducing fine particulate matter (PM 2.5 ) in the United States. Although wildfire smoke (WFS) contains numerous carcinogens and toxicants, its association with cancer incidence remains unclear.
Methods: We examined associations between WFS exposure and cancer incidence in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. The PLCO trial prospectively assessed cancer incidence from enrollment (1993-2001) through 2018. WFS exposure was quantified monthly at participants' residences using near-ground WFS PM 2.5 , WFS black carbon (BC), and satellite-derived WFS plume-day counts from 2006 until first cancer diagnosis or last contact. Guided by evidence that three years of air-pollution exposure can influence the development of EGFR-positive lung adenocarcinoma, WFS exposure was modeled as a time-varying variable using 36-month moving averages preceding each month. Hazard ratios (HRs) were estimated using Cox proportional hazards models stratified by study center, with proportional hazards assumptions verified. Restricted cubic splines were applied to evaluate dose-response relationships. Covariates included age, sex, race and ethnicity, education, smoking history, body mass index, and trial arm.
Results : Among 91,460 PLCO participants with linked WFS exposure data, we identified incident cases of 1,758 lung, 800 colorectal, 1,739 breast, 242 ovarian, 896 bladder, and 1,696 hematopoietic cancers, and 1,127 melanoma during 2006-2018. Median (range) 36-month moving-averages were 0.37 (0.0083-1.72) µg/m 3 for WFS PM 2.5 , 0.0083 (0.00-0.21) µg/m 3 for WFS BC, and 1.94 (0.097-7.18) days for monthly WFS plume-day counts. Restricted cubic splines indicated statistically significant associations (P<0.05) of WFS exposure with increased risks of lung, colorectal, breast, bladder, and hematopoietic cancers, with an approximate linear dose-response observed for most analyses. Moreover, each 1 µg/m 3 increase in the 36-month moving-average of WFS PM 2.5 was associated with higher risks of lung (HR=1.92; 95% CI:
1.18, 3.15), colorectal (2.31; 1.11, 4.81), breast (2.09; 1.34, 3.26), bladder (3.49; 1.66, 7.34), and hematopoietic (1.63; 1.02, 2.60) cancers. No associations were found for ovarian cancer or melanoma. Results for WFS plume-day counts were generally consistent with those for WFS PM 2.5 , whereas associations for WFS BC exposure were observed only for breast and bladder cancers.
Conclusion: WFS exposure was associated with the risk of lung, colorectal, breast, bladder, and hematopoietic cancers. Findings need to be replicated in additional cohorts.
利益披露 Disclosure
Q. Wu, None..
L. Sinclair, None..
V. S. Pankratz, None..
Q. Lan, None..
N. Rothman, None..
R. Jones, None..
S. Zhang, None..
S. Leng, None.