Michael Elten1, Jessy Donelle2, Isac Lima2, Richard T Burnett3, Scott Weichenthal4, David M Stieb5, Perry Hystad6, Aaron van Donkelaar7, Hong Chen8, Lauren A Paul9, Eric Crighton10, Randall V Martin7, Mary Lou Decou11, Wei Luo11, Éric Lavigne12. 1. School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario Canada; Air Health Science Division, Health Canada, Ottawa, Ontario, Canada. 2. ICES UOttawa, Ottawa, Ontario, Canada. 3. Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada. 4. Air Health Science Division, Health Canada, Ottawa, Ontario, Canada; Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Quebec, Canada. 5. School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario Canada; Environmental Health Science and Research Bureau, Health Canada, Vancouver, British Columbia, Canada. 6. College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, USA. 7. Department of Physics and Atmospheric Science, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, USA. 8. ICES UOttawa, Ottawa, Ontario, Canada; Environmental Health Science and Research Bureau, Health Canada, Ottawa, Ontario, Canada; Public Health Ontario, Toronto Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada. 9. Public Health Ontario, Toronto Canada. 10. ICES UOttawa, Ottawa, Ontario, Canada; Department of Geography, Environment and Geomatics, University of Ottawa, Ottawa, Ontario, Canada. 11. Maternal & Infant Health Section, Public Health Agency of Canada, Ottawa, Ontario, Canada. 12. School of Epidemiology and Public Health, University of Ottawa, Ottawa, Ontario Canada; Air Health Science Division, Health Canada, Ottawa, Ontario, Canada. Electronic address: eric.lavigne@canada.ca.
Abstract
BACKGROUND: Studies have reported increasing incidence rates of paediatric diabetes, especially among those aged 0-5 years. Epidemiological evidence linking ambient air pollution to paediatric diabetes remains mixed. OBJECTIVE: This study investigated the association between maternal and early-life exposures to common air pollutants (NO2, PM2.5, O3, and oxidant capacity [Ox; the redox-weighted average of O3 and NO2]) and the incidence of paediatric diabetes in children up to 6 years of age. METHODS: All registered singleton births in Ontario, Ca nada occurring between April 1st, 2006 and March 31st, 2012 were included through linkage from health administrative data. Monthly exposures to NO2, PM2.5, O3, and Ox were estimated across trimesters, the entire pregnancy period and during childhood. Random effects Cox proportional hazards models were used to assess the relationships with paediatric diabetes incidence while controlling for important covariates. We also modelled the shape of concentration-response (CR) relationships. RESULTS: There were 1094 children out of a cohort of 754,698 diagnosed with diabetes before the age of six. O3 exposures during the first trimester of pregnancy were associated with paediatric diabetes incidence (hazard ratio (HR) per interquartile (IQR) increase = 2.00, 95% CI: 1.04-3.86). The CR relationship between O3 during the first trimester and paediatric diabetes incidence appeared to have a risk threshold, in which there was little-to-no risk below 25 ppb of O3, while above this level risk increased sigmoidally. No other associations were observed. CONCLUSION: O3 exposures during a critical period of development were associated with an increased risk of paediatric diabetes incidence. Crown
BACKGROUND: Studies have reported increasing incidence rates of paediatric diabetes, especially among those aged 0-5 years. Epidemiological evidence linking ambient air pollution to paediatric diabetes remains mixed. OBJECTIVE: This study investigated the association between maternal and early-life exposures to common air pollutants (NO2, PM2.5, O3, and oxidant capacity [Ox; the redox-weighted average of O3 and NO2]) and the incidence of paediatric diabetes in children up to 6 years of age. METHODS: All registered singleton births in Ontario, Ca nada occurring between April 1st, 2006 and March 31st, 2012 were included through linkage from health administrative data. Monthly exposures to NO2, PM2.5, O3, and Ox were estimated across trimesters, the entire pregnancy period and during childhood. Random effects Cox proportional hazards models were used to assess the relationships with paediatric diabetes incidence while controlling for important covariates. We also modelled the shape of concentration-response (CR) relationships. RESULTS: There were 1094 children out of a cohort of 754,698 diagnosed with diabetes before the age of six. O3 exposures during the first trimester of pregnancy were associated with paediatric diabetes incidence (hazard ratio (HR) per interquartile (IQR) increase = 2.00, 95% CI: 1.04-3.86). The CR relationship between O3 during the first trimester and paediatric diabetes incidence appeared to have a risk threshold, in which there was little-to-no risk below 25 ppb of O3, while above this level risk increased sigmoidally. No other associations were observed. CONCLUSION:O3 exposures during a critical period of development were associated with an increased risk of paediatric diabetes incidence. Crown