Secondhand Smoke Increases Heart Attack Risk
Over 35,000 U.S. deaths per year from heart disease are due to secondhand smoke, according to the Centers for Disease Control or CDC (Morbidity and Mortality Weekly Report 2002; 51(14): 300-303). Now the agency is warning patients with heart conditions to avoid secondhand smoke in buildings because it may increase their risk of heart attack. Family members also should not smoke around these patients in cars or at home, the CDC says.
Terry Pechacek, the associate director for the CDC's Office on Smoking and Health, issued the alerts after reviewing the literature on secondhand smoke as well as a recent study about hospital admissions in Helena, MT (BMJ 2004; 328: 980-983). That study compared hospital admissions for heart attacks during a 6-month period when an indoor smoking ban was in effect with a period when there was no ban (BMJ 2004; 328: 977-980). Hospital admissions for heart attacks declined by about 40% during the ban, but rebounded after the ban was lifted.
Exposure to secondhand smoke increases the risk of heart disease by about 30%, Mr. Pechacek reported. Even low doses rapidly increase the clumping of blood platelets that may cause clots and lead to heart attacks. Also, tests suggest that a 30-minute dose of secondhand smoke induces changes in the arteries of non-smokers that are similar to those measured in active smokers.
Various studies have shown that eliminating smoking in enclosed public places and workplaces can greatly reduce overall secondhand smoke exposure, and the U.S. Surgeon General has called secondhand smoke a preventable public health hazard. Mr. Pechacek recommended doing more research on the effects of smoking bans on public health. "If future studies replicate the results from the Helena study, the public health implications would be dramatic; thousands of acute myocardial infarction events [heart attacks] among non-smokers in countries around the world could potentially be prevented each year."
Secondhand Smoke Can Cause Lung Cancer
Secondhand smoke is a mixture of the smoke exhaled by smokers (mainstream smoke) as well as the fumes given off by cigarettes, cigars, and pipes (sidestream smoke). In addition to its impact on heart disease, secondhand smoke can greatly increase the risk of developing lung cancer. A landmark study looked at 1,263 lung cancer victims . Nonsmoking spouses who were exposed to their partner's secondhand smoke had an increased lung cancer risk of 18%. That figure rose to 23% if the secondhand smoke exposure was long-term. (See Passive Smoke Increases Lung Cancer Risk)
Young children are particularly sensitive to tobacco. If they are exposed to secondhand smoke, they have a greater risk of contracting asthma, bronchitis, and pneumonia (Tobacco Information and Prevention Source, February 2004, CDC). Sudden infant death syndrome (SIDS) has also been linked to secondhand smoke.
For more information about the dangers of tobacco, see Health Benefits of Smoking Cessation, Nicotine Addiction and Side Effects, and the CDC Tobacco Information and Prevention Source web site.