A study suggesting that e-cigarettes double the risk of a heart attack ignored crucial information on timing.
Last month the Journal of the American Heart Association published a study that claimed “e-cigarette use is an independent risk factor for having had a myocardial infarction.” Based on data from the Population Assessment of Tobacco and Health (PATH), the researchers found that vapers were twice as likely to report heart attacks as subjects who had never smoked or vaped. In a blog post, study co-author Stanton Glantz, a longtime anti-smoking activist who directs the Center for Tobacco Research Control & Education at the University of California, San Francisco, described that finding as “more evidence that e-cigs cause heart attacks.”
But according to Brad Rodu, a tobacco researcher at the University of Louisville, most of the e-cigarette users who reported heart attacks had them before they started vaping, which makes Glantz’s causal inference logically impossible. In a July 11 letter to the journal’s editors, Rodu noted that Glantz and his co-author, Dharma Bhatta, “failed to account for detailed information in that survey on (a) when participants were first told that they had a heart attack and (b) when participants first started using e-cigarettes.”
When Rodu and University of Louisville research economist Nantaporn Plurphanswat looked at that information, they found that most of the 38 vapers who reported heart attacks “were first told that they had a heart attack many years before they first started using e-cigarettes.”
Jacob Sullum – Reason – July 19, 2019.