Short term associations of ambient nitrogen dioxide with daily total, cardiovascular, and respiratory mortality: multilocation analysis in 398 cities
Xia Meng, Cong Liu, Renjie Chen, Francesco Sera, Ana María Vicedo-Cabrera, Ai Milojevic, Yuming Guo, Shilu Tong, Micheline de Sousa Zanotti Stagliorio Coêlho, Paulo Hilário Nascimento Saldiva, Éric Lavigne, Patricia Matus Correa, Nicolás Valdés Ortega, Samuel Osorio, García, Jan Kyselý, Aleš Urban, Hans Orru, Marek Maasikmets, Jouni J. K. Jaakkola, Niilo Ryti, Veronika Huber, Alexandra Schneider, Klea Katsouyanni, Antonis Analitis, Masahiro Hashizume, Yasushi Honda, Chris Fook Sheng Ng, Baltazar Nunes, João Paulo Teixeira, Iulian‐Horia Holobâcă, Simona Fratianni, Ho Kim, Aurelio Tobı́as, Carmen Íñiguez, Bertil Forsberg, Christofer Åström, Martina S. Ragettli, Yue Leon Guo, Shih‐Chun Pan, Shanshan Li, Michelle L. Bell, Antonella Zanobetti, Joel Schwartz, Tangchun Wu, Antonio Gasparrini, Haidong Kan
Abstract
Abstract Objective To evaluate the short term associations between nitrogen dioxide (NO 2 ) and total, cardiovascular, and respiratory mortality across multiple countries/regions worldwide, using a uniform analytical protocol. Design Two stage, time series approach, with overdispersed generalised linear models and multilevel meta-analysis. Setting 398 cities in 22 low to high income countries/regions. Main outcome measures Daily deaths from total (62.8 million), cardiovascular (19.7 million), and respiratory (5.5 million) causes between 1973 and 2018. Results On average, a 10 μg/m 3 increase in NO 2 concentration on lag 1 day (previous day) was associated with 0.46% (95% confidence interval 0.36% to 0.57%), 0.37% (0.22% to 0.51%), and 0.47% (0.21% to 0.72%) increases in total, cardiovascular, and respiratory mortality, respectively. These associations remained robust after adjusting for co-pollutants (particulate matter with aerodynamic diameter ≤10 μm or ≤2.5 μm (PM 10 and PM 2.5 , respectively), ozone, sulfur dioxide, and carbon monoxide). The pooled concentration-response curves for all three causes were almost linear without discernible thresholds. The proportion of deaths attributable to NO 2 concentration above the counterfactual zero level was 1.23% (95% confidence interval 0.96% to 1.51%) across the 398 cities. Conclusions This multilocation study provides key evidence on the independent and linear associations between short term exposure to NO 2 and increased risk of total, cardiovascular, and respiratory mortality, suggesting that health benefits would be achieved by tightening the guidelines and regulatory limits of NO 2 .