title: The association between ambient air quality and cardiac rate and rhythm in ambulatory subjects.
abstract: BACKGROUND
  Acute increases in ambient air pollution have been associated with increased hospitalization for cardiac diseases and stroke. Triggering of cardiac arrhythmia by changes in air quality could theoretically predispose individuals to cardiac arrest or heart failure, or stroke through precipitation of atrial fibrillation. We investigated the association between air quality and cardiac rate and rhythm characteristics measured by ambulatory cardiac monitoring.
  
  
  RESULTS
  Daily ambient 3-h maximum concentrations of ozone, nitrogen dioxide and fine particulate matter, and an index summarizing these pollutants called the Air Quality Health Index (AQHI) were compared to the results of 24-h ambulatory cardiac monitoring performed for clinical purposes in 8662 patients and analyzed at the University of Ottawa Heart Institute, Canada, between 2004 and 2009. An interquartile increase in the daily 3 h- maximum AQHI was associated with a 0.9% (95% CI 0.3%, 1.5%) increase in the daily maximum heart rate and a 1.17% (95% CI 1.07%, 1.29%) increase in heart block frequency. An interquartile increase in NO2 was associated with an increase in the percentage of time in atrial fibrillation of 4.39% (-0.15, 9.15) among those ≤50 years old, and 7.1% (0.24, 14.5) among males.
  
  
  CONCLUSIONS
  We found evidence that air pollution may affect cardiac rate and rhythm. This may be one mechanism partially explaining the increase in strokes and cardiac events observed on days of higher air pollution.
authors.affiliation: Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, 50 Columbine Driveway, Ottawa, ON K1A 0K9, Canada. Electronic address: sabit_cakmak@hc-sc.gc.ca.
authors.forename: Sabit
authors.initials: S
authors.lastname: Cakmak
authors.affiliation: Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, 200 Eglantine Driveway, Ottawa, ON K1A 0K9, Canada. Electronic address: Lisa.Marie.Kauri@hc-sc.gc.ca.
authors.forename: Lisa
authors.initials: L
authors.lastname: Kauri
authors.affiliation: Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, 200 Eglantine Driveway, Ottawa, ON K1A 0K9, Canada. Electronic address: Robin.Shutt@hc-sc.gc.ca.
authors.forename: Robin
authors.initials: R
authors.lastname: Shutt
authors.affiliation: Air Quality Health Effects Research Section, Biostatistics and Epidemiology Division, Environmental Health Sciences and Research Bureau, Health Canada, 200 Eglantine Driveway,Ottawa, ON K1A 0K9, Canada. Electronic address: Ling_Liu@hc-sc.gc.ca.
authors.forename: Ling
authors.initials: L
authors.lastname: Liu
authors.affiliation: Division of Cardiology at the University of Ottawa Heart Institute, 40 Ruskin St., Ottawa, ON K1Y 4W7, Canada. Electronic address: MGreen@ottawaheart.ca.
authors.forename: Martin S
authors.initials: MS
authors.lastname: Green
authors.affiliation: University of Ottawa Heart Institute, 40 Ruskin St., Ottawa, ON K1Y 4W7, Canada. Electronic address: MMulholland@ottawaheart.ca.
authors.forename: Marie
authors.initials: M
authors.lastname: Mulholland
authors.affiliation: Risk Analysis and Modelling Section, Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada. Electronic address: Dave.Stieb@hc-sc.gc.ca.
authors.forename: Dave
authors.initials: D
authors.lastname: Stieb
authors.affiliation: Population Studies Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa Hospital Research Institute, Ottawa, ON, Canada. Electronic address: R.Dales@hc-sc.gc.ca.
authors.forename: Robert
authors.initials: R
authors.lastname: Dales
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution; D000553:Ambulatory Care; D001145:Arrhythmias, Cardiac / Q000453:epidemiology*; D002648:Child; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D000393:Air Pollutants
keywords: Air pollution; Cardiac rhythm; Environment; Epidemiology