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We find no evidence that legislated U.S. smoking bans were associated with
short‐term reductions in hospital admissions for acute myocardial infarction or other
diseases in the elderly, children or working‐age adults. We find some evidence that
smoking bans are associated with a reduced all‐cause mortality rate among the elderly
(‐1.4%) but only at the 10% significance level.
We also show that there is wide year‐to‐year variation in myocardial infarction
death and admission rates even in large regions such as counties and hospital
catchment areas. Comparisons of small samples (which represent subsamples of our
data and are similar to the samples used in the previous published literature) might
have led to atypical findings. It is also possible that comparisons showing increases in
cardiovascular events after a smoking ban were not submitted for publication because
the results were considered implausible. Hence, the true distribution from single
regions would include both increases and decreases in events and a mean close to zero,
while the published record would show only decreases in events. Thus, publication bias
could plausibly explain why dramatic short‐term public health improvements were
seen in prior studies of smoking bans.
Our study focuses only on the health effects of smoking bans. Future research
should estimate non‐health related benefits of these bans to non‐smokers. Prior to a
smoking ban, non‐smokers at risk for respiratory symptoms or cardiovascular events
might have avoided businesses with high ETS levels. After a ban, non‐smokers could
gain comfortable access to these businesses, but based on our findings in this study, this
benefit would not also result in reduced hospitalization or death rates. Our study
design plausibly identifies only short‐term benefits of smoking bans (as has the study
designs used by previous studies). We cannot analyze whether smoking bans improve
long‐term trends for chronic cardiovascular disease or lung cancer. In addition,
smoking bans may induce smokers to quit or discourage nonsmokers from starting
smoking. These potential long‐term benefits will not be apparent in study of short‐term
outcomes and would benefit from further study.