title: Long-term exposure to outdoor air pollution and incidence of cardiovascular diseases.
abstract: BACKGROUND
  Evidence based largely on US cohorts suggests that long-term exposure to fine particulate matter is associated with cardiovascular mortality. There is less evidence for other pollutants and for cardiovascular morbidity. By using a cohort of 836,557 patients age 40 to 89 years registered with 205 English general practices in 2003, we investigated relationships between ambient outdoor air pollution and incident myocardial infarction, stroke, arrhythmia, and heart failure over a 5-year period.
  
  
  METHODS
  Events were identified from primary care records, hospital admissions, and death certificates. Annual average concentrations in 2002 for particulate matter with a median aerodynamic diameter <10 (PM10) and <2.5 microns, nitrogen dioxide (NO2), ozone, and sulfur dioxide at a 1 × 1 km resolution were derived from emission-based models and linked to residential postcode. Analyses were performed using Cox proportional hazards models adjusting for relevant confounders, including social and economic deprivation and smoking.
  
  
  RESULTS
  While evidence was weak for relationships with myocardial infarction, stroke, or arrhythmia, we found consistent associations between pollutant concentrations and incident cases of heart failure. An interquartile range change in PM10 and in NO2 (3.0 and 10.7 µg/m, respectively) both produced a hazard ratio of 1.06 (95% confidence interval = 1.01-1.11) after adjustment for confounders. There was some evidence that these effects were greater in more affluent areas.
  
  
  CONCLUSIONS
  This study of an English national cohort found evidence linking long-term exposure to particulate matter and NO2 with the development of heart failure. We did not, however, replicate associations for other cardiovascular outcomes that have been reported elsewhere.
authors.affiliation: Division of Population Health Sciences and Education and MRC-HPA Centre for Environment and Health, St George's, University of London, London, United Kingdom. atkinson@sgul.ac.uk
authors.forename: Richard W
authors.initials: RW
authors.lastname: Atkinson
authors.forename: Iain M
authors.initials: IM
authors.lastname: Carey
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Kent
authors.forename: Tjeerd P
authors.initials: TP
authors.lastname: van Staa
authors.forename: H Ross
authors.initials: HR
authors.lastname: Anderson
authors.forename: Derek G
authors.initials: DG
authors.lastname: Cook
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis / Q000633:toxicity*; D000397:Air Pollution / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D002318:Cardiovascular Diseases / Q000139:chemically induced* / Q000453:epidemiology; D016208:Databases, Factual; D004739:England / Q000453:epidemiology; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D009585:Nitrogen Dioxide / Q000032:analysis / Q000633:toxicity; D010126:Ozone / Q000032:analysis / Q000633:toxicity; D052638:Particulate Matter / Q000032:analysis / Q000633:toxicity; D016016:Proportional Hazards Models; D013458:Sulfur Dioxide / Q000032:analysis / Q000633:toxicity
chemical_list: D000393:Air Pollutants; D052638:Particulate Matter; D013458:Sulfur Dioxide; D010126:Ozone; D009585:Nitrogen Dioxide