title: Reduction in asthma-related emergency department visits after implementation of a smoke-free law.
abstract: BACKGROUND
  Secondhand tobacco smoke increases the risk for the development and increasing severity of asthma among adults and children. Reducing exposure to secondhand smoke decreases symptomatic exacerbations among patients with asthma. Emergency department (ED) visits for asthma were assessed before and after the implementation of smoke-free legislation in Lexington-Fayette County, Ky.
  
  
  OBJECTIVE
  To evaluate the effects of a smoke-free law on the rate of ED visits for asthma.
  
  
  METHODS
  The study included ED visits for asthma from 4 hospitals in Lexington-Fayette County, Ky. Age-adjusted rates of asthma ED visits were determined. Poisson regression analysis of ED visits from January 1, 2001, to December 31, 2006 compared the ED visit rates between prelaw and postlaw, adjusting for seasonality, secular trends over time, and differences among demographic subgroups. The actual rates were graphed with the Poisson curve showing the rates predicted by the model. A second prediction curve was generated to show the projected rates in the postlaw period if the law had not been implemented.
  
  
  RESULTS
  Adjusting for seasonality, secular trends, and demographic characteristics, ED visits for asthma declined 22% from prelaw to postlaw (P < .0001; 95% CI, 14% to 29%). The rate of decline was 24% in adults age 20 years and older (P < .0001), whereas the decrease among children 19 years or younger was 18% (P = .01).
  
  
  CONCLUSIONS
  Although this study did not establish causation, the smoke-free law was associated with fewer asthma ED visits among both children and adults, with a more significant decline among adults.
authors.affiliation: College of Nursing, University of Kentucky, Lexington, Kentucky, USA.
authors.forename: Mary Kay
authors.initials: MK
authors.lastname: Rayens
authors.forename: Patricia V
authors.initials: PV
authors.lastname: Burkhart
authors.forename: Mei
authors.initials: M
authors.lastname: Zhang
authors.forename: Seongjik
authors.initials: S
authors.lastname: Lee
authors.forename: Debra K
authors.initials: DK
authors.lastname: Moser
authors.forename: David
authors.initials: D
authors.lastname: Mannino
authors.forename: Ellen J
authors.initials: EJ
authors.lastname: Hahn
mesh_terms: D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000453:epidemiology* / Q000209:etiology / Q000276:immunology; D002648:Child; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007629:Kentucky; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D012044:Regression Analysis; D012907:Smoking / Q000009:adverse effects / Q000331:legislation & jurisprudence*; D014028:Tobacco Smoke Pollution / Q000009:adverse effects / Q000331:legislation & jurisprudence*
chemical_list: D014028:Tobacco Smoke Pollution