title: Cardiovascular disease and air pollution in Scotland: no association or insufficient data and study design?
abstract: BACKGROUND
  Coronary heart disease and stroke are leading causes of mortality and ill health in Scotland, and clear associations have been found in previous studies between air pollution and cardiovascular disease. This study aimed to use routinely available data to examine whether there is any evidence of an association between short-term exposure to particulate matter (measured as PM₁₀, particles less than 10 micrograms per cubic metre) and hospital admissions due to cardiovascular disease, in the two largest cities in Scotland during the years 2000 to 2006.
  
  
  METHODS
  The study utilised an ecological time series design, and the analysis was based on overdispersed Poisson log-linear models.
  
  
  RESULTS
  No consistent associations were found between PM₁₀ concentrations and cardiovascular hospital admissions in either of the cities studied, as all of the estimated relative risks were close to one, and all but one of the associated 95% confidence intervals contained the null risk of one.
  
  
  CONCLUSIONS
  This study suggests that in small cities, where air quality is relatively good, then either PM₁₀ concentrations have no effect on cardiovascular ill health, or that the routinely available data and the corresponding study design are not sufficient to detect an association.
authors.affiliation: NHS Lothian, Edinburgh, UK.
authors.forename: Lorna J
authors.initials: LJ
authors.lastname: Willocks
authors.forename: Abita
authors.initials: A
authors.lastname: Bhaskar
authors.forename: Colin N
authors.initials: CN
authors.lastname: Ramsay
authors.forename: Duncan
authors.initials: D
authors.lastname: Lee
authors.forename: David H
authors.initials: DH
authors.lastname: Brewster
authors.forename: Colin M
authors.initials: CM
authors.lastname: Fischbacher
authors.forename: James
authors.initials: J
authors.lastname: Chalmers
authors.forename: George
authors.initials: G
authors.lastname: Morris
authors.forename: E Marian
authors.initials: EM
authors.lastname: Scott
mesh_terms: D000397:Air Pollution / Q000009:adverse effects*; D002947:Cities; D003327:Coronary Disease / Q000453:epidemiology* / Q000628:therapy; D003627:Data Interpretation, Statistical; D004781:Environmental Exposure / Q000009:adverse effects*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D016014:Linear Models; D052638:Particulate Matter / Q000032:analysis*; D012107:Research Design; D012307:Risk Factors; D012606:Scotland / Q000453:epidemiology; D020521:Stroke / Q000453:epidemiology* / Q000628:therapy; D014504:Urban Health / Q000639:trends*
chemical_list: D052638:Particulate Matter