Andersen Zorana Jovanovic, de Nazelle Audrey, Mendez Michelle Ann, Garcia-Aymerich Judith, Hertel Ole, Tjønneland Anne, Overvad Kim, Raaschou-Nielsen Ole, Nieuwenhuijsen Mark J
Center for Epidemiology and Screening, Department of Public Health, University of Copenhagen, Copenhagen, Denmark.
Environ Health Perspect. 2015 Jun;123(6):557-63. doi: 10.1289/ehp.1408698. Epub 2015 Jan 27.
Physical activity reduces, whereas exposure to air pollution increases, the risk of premature mortality. Physical activity amplifies respiratory uptake and deposition of air pollutants in the lung, which may augment acute harmful effects of air pollution during exercise.
We aimed to examine whether benefits of physical activity on mortality are moderated by long-term exposure to high air pollution levels in an urban setting.
A total of 52,061 subjects (50-65 years of age) from the Danish Diet, Cancer, and Health cohort, living in Aarhus and Copenhagen, reported data on physical activity in 1993-1997 and were followed until 2010. High exposure to air pollution was defined as the upper 25th percentile of modeled nitrogen dioxide (NO2) levels at residential addresses. We associated participation in sports, cycling, gardening, and walking with total and cause-specific mortality by Cox regression, and introduced NO2 as an interaction term.
In total, 5,534 subjects died: 2,864 from cancer, 1,285 from cardiovascular disease, 354 from respiratory disease, and 122 from diabetes. Significant inverse associations of participation in sports, cycling, and gardening with total, cardiovascular, and diabetes mortality were not modified by NO2. Reductions in respiratory mortality associated with cycling and gardening were more pronounced among participants with moderate/low NO2 [hazard ratio (HR) = 0.55; 95% CI: 0.42, 0.72 and 0.55; 95% CI: 0.41, 0.73, respectively] than with high NO2 exposure (HR = 0.77; 95% CI: 0.54, 1.11 and HR = 0.81; 95% CI: 0.55, 1.18, p-interaction = 0.09 and 0.02, respectively).
In general, exposure to high levels of traffic-related air pollution did not modify associations, indicating beneficial effects of physical activity on mortality. These novel findings require replication in other study populations.
体育活动可降低过早死亡风险，而暴露于空气污染中会增加过早死亡风险。体育活动会增强肺部对空气污染物的呼吸摄取和沉积，这可能会加剧运动期间空气污染的急性有害影响。
我们旨在研究在城市环境中，长期暴露于高空气污染水平是否会调节体育活动对死亡率的益处。
来自丹麦饮食、癌症和健康队列的52061名受试者（年龄在50 - 65岁之间），居住在奥胡斯和哥本哈根，报告了1993 - 1997年的体育活动数据，并随访至2010年。高空气污染暴露定义为居住地址处模拟二氧化氮（NO₂）水平的第25百分位数以上。我们通过Cox回归将参与运动、骑自行车、园艺和步行与全因死亡率及特定病因死亡率相关联，并将NO₂作为交互项引入。
共有5534名受试者死亡：2864人死于癌症，1285人死于心血管疾病，354人死于呼吸系统疾病，122人死于糖尿病。参与运动、骑自行车和园艺与全因、心血管和糖尿病死亡率之间的显著负相关未被NO₂改变。与中等/低NO₂暴露组相比，骑自行车和园艺与呼吸系统死亡率降低的关联在中等/低NO₂暴露组中更明显[风险比（HR） = 0.55；95%置信区间：0.42，0.72和0.55；95%置信区间：0.41，0.73]，而在高NO₂暴露组中则不然（HR = 0.77；95%置信区间：0.54，1.11和HR = 0.81；95%置信区间：0.55，1.18，交互作用p值分别为0.09和0.02）。
总体而言，暴露于高水平的交通相关空气污染并未改变这种关联，表明体育活动对死亡率有益。这些新发现需要在其他研究人群中进行重复验证。
