Colorado smoking ban: no impact on heart attacks
The striking implication was: eliminating second-hand smoke saves lives by reducing heart disease.
There were two problems with these claims. First, the declines, based on small numbers of observations, were actually consistent with random variation. Second, none of the reports accounted for the long-term downward trend in heart disease in the United States. They credited no-smoking intervention with the lower number of AMIs at a time when rates were declining nationwide.
In 2011, I documented that state-wide smoking bans in California, Utah, Delaware, South Dakota, New York and Florida had little or no immediate measurable effect on AMI deaths. The study, published in the Journal of Community Health, eliminated the “tiny-number” problem and factored in the national downward trend in AMI deaths.
I discussed these findings on my blog, but the work was largely ignored, until now.
Recently, researchers from three Colorado institutions reported AMI rates before and after a statewide smoking ban there; their work appears in the American Journal of Medicine. (Thanks to Chris Snowdon, who also blogged about it here).
Paul Basel and colleagues found that “No signiﬁcant reduction in [AMI] rates was observed” after the Colorado ban was implemented. They also referred to our study:
[The Rodu et al.] study compared the decline in [AMI] mortality in 6 states with smoke-free ordinances, with the average decline among 44 states unaffected by smoke-free policy. No state with a smoke-free ordinance had a signiﬁcantly lower observed [AMI] mortality compared with that expected by the nationwide secular decrease in states without the ordinance. This emerging evidence highlights the importance of accounting for secular trends in [AMI] incidence before deﬁnitive attribution to smoke-free ordinances can be made.
It is comforting to see unfounded second-hand smoke claims corrected, particularly in the pages of a prestigious journal.