Reduction in asthma-related emergency department visits after implementation of a smoke-free law
Received 21 December 2007; received in revised form 26 June 2008; accepted 26 June 2008. published online 11 August 2008.
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).
Conclusion
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.
aCollege of Nursing, University of Kentucky, Lexington, Ky
bCollege of Public Health, University of Kentucky, Lexington, Ky
cCollege of Medicine, University of Kentucky, Lexington, Ky
Reprint requests: Ellen J. Hahn, DNS, RN, 760 Rose St, Lexington, KY 40536-0232.
Supported by the Flight Attendant Medical Research Institute.
Disclosure of potential conflict of interest: E. J. Hahn receives grant support from the Flight Attendant Medical Research Institute. D. K. Moser receives grant support from the National Institutes of Health–National Institute of Nursing Research and the National Institutes of Health–Nation Heart, Lung, and Blood Institute. D. Mannino is on the advisory board for GlaxoSmithKline and Pfizer and the Data Safety Monitoring Board for Boehringer-Ingelheim; receives grant support from GlaxoSmithKline, Pfizer, and Novartis; and has provided legal consultation or expert witness testimony in cases related to secondhand smoke and diacetyl exposure. M. K. Rayens receives grant support from the Flight Attendant Medical Research Institute. The rest of the authors have declared that they have no conflict of interest.
ABSTRACT