Declines in acute myocardial infarction after smoke-free laws and individual risk attributable to secondhand smoke.
BACKGROUND
The estimated effects of recent pubic and workplace smoking restriction laws suggest that they produce significant declines in community rates of heart attack. The consistency of these declines with existing estimates of the relative risk of heart attack in individuals attributable to passive smoking exposure is poorly understood. The objective is to determine the consistency of estimates of reductions in community rates of heart attacks resulting from smoking restriction laws with estimates of the relative risk of heart disease in individuals exposed to passive smoking.


RESULTS
Meta-analyses of existing estimates of declines in community rates were compared with a mathematical model of the relationship between individual risk and community rates. The outcome measure is the ratio of community rates of acute myocardial infarction (after divided by before implementation of a smoking restriction law). There is a significant drop in the rate of acute myocardial infarction hospital admissions associated with the implementation of strong smoke-free legislation. The primary reason for heterogeneity in results of different studies is the duration of follow-up after adoption of the law. The pooled random-effects estimate of the rate of acute myocardial infarction hospitalization 12 months after implementation of the law is 0.83 (95% confidence interval, 0.80 to 0.87), and this benefit grows with time. This drop in admissions is consistent with a range of plausible individual risk and exposure scenarios.


CONCLUSIONS
Passage of strong smoke-free legislation produces rapid and substantial benefits in terms of reduced acute myocardial infarctions, and these benefits grow with time.
Lightwood
James M
JM
Department of Clinical Pharmacy, University of California, 3333 California St, Suite 420, San Francisco, CA 94118, USA. lightwoodj@pharmacy.ucsf.edu
Glantz
Stanton A
SA
D000208:Acute Disease; D003120:Colorado / Q000453:epidemiology; D003198:Computer Simulation; D016001:Confidence Intervals; D004781:Environmental Exposure / Q000009:adverse effects; D006801:Humans; D007558:Italy / Q000453:epidemiology; D015201:Meta-Analysis as Topic; D009009:Montana / Q000453:epidemiology; D009203:Myocardial Infarction / Q000453:epidemiology* / Q000517:prevention & control*; D012306:Risk; D014028:Tobacco Smoke Pollution / Q000331:legislation & jurisprudence* / Q000517:prevention & control*
D014028:Tobacco Smoke Pollution