Yang Jun, Sakhvidi Mohammad Javad Zare, de Hoogh Kees, Vienneau Danielle, Siemiatyck Jack, Zins Marie, Goldberg Marcel, Chen Jie, Lequy Emeline, Jacquemin Bénédicte
Univ. Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France; Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China.
Univ. Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France.
Environ Int. 2021 Dec;157:106805. doi: 10.1016/j.envint.2021.106805. Epub 2021 Aug 7.
The current evidence on health effects of long-term exposure to outdoor airborne black carbon (BC) exposure remains scarce.
To examine the association between long-term exposure to BC and mortality in a large population-based French cohort, with 28 years of follow-up.
Data from the GAZEL cohort were collected between 1989 and 2017. Land use regression model with temporal extrapolation wa used to estimate yearly BC and PM exposure at the residential addresses from 1989 until censoring for 19,906 participants. Time-varying Cox models with attained age as time-scale was used to estimate the associations between BC and all-cause and cardiovascular mortality, after adjusting for individual and area-level covariates. To handle confounding by PM, we used the residual of BC regressed on PM as an alternate exposure variable. For all-cause mortality, we also examined effect modification by sex, smoking status, BMI and fruit/vegetable intake.
The median of 20-year moving average of BC exposure was 2.02 10/m in study population. We found significant associations between BC exposure and all-cause mortality (n = 2357) using both 20-year moving average of BC and residual of BC, with corresponding hazard ratios (HR) of 1.14 (95 %CI: 1.07-1.22) and 1.17 (95 %CI: 1.10-1.24) for an inter-quartile range (IQR) increase (0.86 10/m for BC and 0.57 10/m for residual of BC). We found a similar association between BC and cardiovascular mortality (n = 277) with a HR of 1.15 (95 %CI: 0.95-1.38). The dose-response relationship between BC and all-cause mortality was monotonic but nonlinear with a steeper slope at high BC levels. In addition, the effect of BC was higher among never-smokers and among those having fruit/vegetables less than twice a week.
There was a positive association between long-term exposure to BC and increased mortality risk, reinforcing the emerging evidence that BC is a harmful component of PM.
关于长期暴露于室外空气中黑碳（BC）对健康影响的现有证据仍然很少。
在一个以人群为基础的大型法国队列中，进行28年的随访，研究长期暴露于BC与死亡率之间的关联。
收集1989年至2017年GAZEL队列的数据。使用带有时间外推的土地利用回归模型来估计1989年至19906名参与者被审查时其居住地址的年度BC和PM暴露量。以达到的年龄作为时间尺度的时变Cox模型用于估计BC与全因死亡率和心血管死亡率之间的关联，同时对个体和地区层面的协变量进行了调整。为处理PM的混杂影响，我们使用将BC对PM进行回归后的残差作为替代暴露变量。对于全因死亡率，我们还研究了性别、吸烟状况、BMI和水果/蔬菜摄入量的效应修正情况。
研究人群中BC暴露的20年移动平均值中位数为2.02 μg/m³。我们发现，使用BC的20年移动平均值和BC残差，BC暴露与全因死亡率（n = 2357）之间均存在显著关联，四分位间距（IQR）增加（BC为0.86 μg/m³，BC残差为0.57 μg/m³）时，相应的风险比（HR）分别为1.14（95%CI：1.07 - 1.22）和1.17（95%CI：1.10 - 1.24）。我们发现BC与心血管死亡率（n = 277）之间存在类似关联，HR为1.15（95%CI：0.95 - 1.38）。BC与全因死亡率之间的剂量反应关系是单调的，但呈非线性，在高BC水平时斜率更陡。此外，在从不吸烟者以及每周食用水果/蔬菜少于两次的人群中，BC的影响更大。
长期暴露于BC与死亡风险增加之间存在正相关，这进一步证明了BC是PM的有害成分这一新兴证据。
