Heartstopping Discovery
Anti-smoking activist Stanton Glantz is claiming that a smoking ban in Helena, Montana, cut heart attacks in half. "This striking finding suggests that protecting people from toxins in secondhand smoke not only makes life more pleasant, it immediately starts saving lives," he says.
Glantz and his co-authors have not published their research, which was reported at a recent meeting of the American College of Cardiology, so it is hard to evaluate. But descriptions of their findings, which were based on hospital records from the six months when the ban was in effect (it was suspended due to a legal challenge), prompt a few observations and questions:
1. Assuming the decrease in heart attacks was not coincidental, it could have been due to smokers who cut back or quit as a result of the ban rather than the elimination of secondhand smoke.
2. Even taken at face value, these data do not indicate that secondhand smoke causes heart disease, as Glantz and his fellow activists claim. Acute effects of the kind he is suggesting would be limited to people already suffering from heart problems. Robert West, a smoking cessation expert interviewed by the British magazine New Scientist, speculates that exposure to smoke triggers production of white blood cells, which generate clotting agents when they break down. "If someone is teetering on the brink of a heart attack," he says, "this clotting is likely to tip them over."
3. According to Glantz, the actual decrease in heart attacks was about four per month on average, from around seven to around three. Why didn't Glantz look at heart attacks in a big city with a smoking ban, such as Los Angeles or San Francisco, where the samples are much larger and a dramatic drop like the one he is claiming would have been obvious? Indeed, why haven't hospitals in such cities noticed that they are seeing about half as many heart attacks as they used to?
If you believe Glantz, the entire state of California should have seen a big drop in heart attacks when it banned smoking in all workplaces. Likewise Delaware. And now that New York state has adopted a similar ban, heart attacks should drop precipitously there as well. Or is there something special about the way hearts work in Helena?