Study supports link between passive exposure to cigarette smoke and risk of heart disease

Non-smokers who are exposed to environmental tobacco smoke for at least 30 minutes a day are at far greater risk of developing acute coronary syndromes compared with people who are not exposed, finds a study in Tobacco Control.

These findings support the role of environmental tobacco smoke in the development of adverse cardiac events.

A total of 847 individuals with a first event of acute coronary syndromes and 1,078 cardiovascular disease-free controls were included in the study. Participants were asked whether they were currently exposed to tobacco smoke from other people (home and/or work) for more than 30 minutes a day. They were also asked how many years they had been exposed. Because these were self reported assessments and prone to bias, the results were compared to reports obtained from subjects’ relatives or friends.

Almost nine out of 10 of the patients and six out of 10 of the controls were passively exposed to tobacco smoke. Never smokers reporting occasional or regular exposure to cigarette smoke had a 47% higher risk of developing acute coronary syndromes compared with never smokers who were not exposed to environmental tobacco smoke.

Exposure at work was associated with a greater risk compared to home exposure. The risk of acute coronary syndromes was also raised in active smokers regularly exposed to environmental tobacco smoke.

These findings support the hypothesis stated by other investigators that occasional and regular exposure to tobacco smoke can significantly increase the risk of developing acute coronary syndromes among non-smokers or never smokers, say the authors.

The only safe way to protect non-smokers from exposure to cigarette smoke is to eliminate this health hazard from public places and workplaces, as well as from the home. A ban on smoking in workplaces might be an effective way to reduce exposure to environmental tobacco smoke, they conclude.