title: Traffic pollution and the incidence of cardiorespiratory outcomes in an adult cohort in London.
abstract: OBJECTIVE
  The epidemiological evidence for adverse health effects of long-term exposure to air and noise pollution from traffic is not coherent. Further, the relative roles of background versus near traffic pollution concentrations in this process are unclear. We investigated relationships between modelled concentrations of air and noise pollution from traffic and incident cardiorespiratory disease in London.
  
  
  METHODS
  Among 211 016 adults aged 40-79 years registered in 75 Greater London practices between 2005 and 2011, the first diagnosis for a range of cardiovascular and respiratory outcomes were identified from primary care and hospital records. Annual baseline concentrations for nitrogen oxide (NOx), particulate matter with a median aerodynamic diameter <2.5 μm (PM2.5) attributable to exhaust and non-exhaust sources, traffic intensity and noise were estimated at 20 m2resolution from dispersion models, linked to clinical data via residential postcode. HRs were adjusted for confounders including smoking and area deprivation.
  
  
  RESULTS
  The largest observed associations were between traffic-related air pollution and heart failure (HR=1.10 for 20 μg/m3change in NOx, 95% CI 1.01 to 1.21). However, no other outcomes were consistently associated with any of the pollution indicators, including noise. The greater variations in modelled air pollution from traffic between practices, versus within, hampered meaningful fine spatial scale analyses.
  
  
  CONCLUSIONS
  The associations observed with heart failure may suggest exacerbatory effects rather than underlying chronic disease. However, the overall failure to observe wider associations with traffic pollution may reflect that exposure estimates based on residence inadequately represent the relevant pattern of personal exposure, and future studies must address this issue.
authors.affiliation: Population Health Research Institute, St George's University of London, London, UK.
authors.forename: I M
authors.identifier: http://orcid.org/0000-0003-1099-8460
authors.initials: IM
authors.lastname: Carey
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, London, UK.
authors.forename: H R
authors.initials: HR
authors.lastname: Anderson
authors.affiliation: Population Health Research Institute, St George's University of London, London, UK.
authors.forename: R W
authors.initials: RW
authors.lastname: Atkinson
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Beevers
authors.affiliation: Population Health Research Institute, St George's University of London, London, UK.
authors.forename: D G
authors.initials: DG
authors.lastname: Cook
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, London, UK.
authors.forename: D
authors.initials: D
authors.lastname: Dajnak
authors.affiliation: UK Small Area Health Statistics Unit, MRC-PHE Centre for Environment and Health, Imperial College, London, UK.
authors.forename: J
authors.initials: J
authors.lastname: Gulliver
authors.affiliation: MRC-PHE Centre for Environment and Health, King's College London, London, UK.
authors.forename: F J
authors.initials: FJ
authors.lastname: Kelly
mesh_terms: D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000009:adverse effects*; D000397:Air Pollution / Q000009:adverse effects*; D002318:Cardiovascular Diseases / Q000139:chemically induced / Q000453:epidemiology; D015331:Cohort Studies; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D006333:Heart Failure / Q000139:chemically induced* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D008131:London / Q000453:epidemiology; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D052638:Particulate Matter; D016016:Proportional Hazards Models; D012140:Respiratory Tract Diseases / Q000139:chemically induced / Q000453:epidemiology; D012307:Risk Factors; D001335:Vehicle Emissions
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D001335:Vehicle Emissions