title: Cardiac arrhythmia emergency room visits and environmental air pollution in Sao Paulo, Brazil.
abstract: OBJECTIVE
  Air-pollution exposure has been associated with increased cardiovascular hospital admissions and mortality in time-series studies. We evaluated the relation between air pollutants and emergency room (ER) visits because of cardiac arrhythmia in a cardiology hospital.
  
  
  METHODS
  In a time-series study, we evaluated the association between the emergency room visits as a result of cardiac arrhythmia and daily variations in SO(2), CO, NO(2), O(3) and PM(10), from January 1998 to August 1999. The cases of arrhythmia were modelled using generalised linear Poisson regression models, controlling for seasonality (short-term and long-term trend), and weather.
  
  
  RESULTS
  Interquartile range increases in CO (1.5 ppm), NO(2) (49,5 microg/m(3)) and PM(10) (22.2 microg/m(3)) on the concurrent day were associated with increases of 12.3% (95% CI: 7.6% to 17.2%), 10.4% (95% CI: 5.2% to 15.9%) and 6.7% (95% CI: 1.2% to 12.4%) in arrhythmia ER visits, respectively. PM(10), CO and NO(2) effects were dose-dependent and gaseous pollutants had thresholds. Only CO effect resisted estimates in models with more than one pollutant.
  
  
  CONCLUSIONS
  Our results showed that air pollutant effects on arrhythmia are predominantly acute starting at concentrations below air quality standards, and the association with CO and NO(2) suggests a relevant role for pollution caused by cars.
authors.affiliation: Pulmonary Division of Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil.
authors.forename: U P
authors.initials: UP
authors.lastname: Santos
authors.forename: M
authors.initials: M
authors.lastname: Terra-Filho
authors.forename: C A
authors.initials: CA
authors.lastname: Lin
authors.forename: L A A
authors.initials: LA
authors.lastname: Pereira
authors.forename: T C B
authors.initials: TC
authors.lastname: Vieira
authors.forename: P H N
authors.initials: PH
authors.lastname: Saldiva
authors.forename: A L F
authors.initials: AL
authors.lastname: Braga
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000393:Air Pollutants / Q000009:adverse effects / Q000032:analysis; D000397:Air Pollution / Q000009:adverse effects*; D001145:Arrhythmias, Cardiac / Q000453:epidemiology / Q000209:etiology*; D001938:Brazil / Q000453:epidemiology; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D062665:Epidemiological Monitoring; D005260:Female; D006801:Humans; D006813:Humidity; D008297:Male; D008875:Middle Aged; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data; D013696:Temperature
chemical_list: D000393:Air Pollutants