Healthy Living Newsletter
Secondhand Smoke... IT ALL COUNTS
When Rita was growing up in the 1950s, both of her parents smoked. The living room was nearly always filled with bluish-grey clouds, particularly after meals. She and her brother remember choking for breath in the back seat when they took family trips in their Volkswagen.
At university in the 1960s, most students and professors smoked in the classroom. And when she took her first job at a newspaper, a cloud of smoke always hovered over the city desk.
Today when Rita fills out health questionnaires, she marks the box “never smoked” but always feels she should add an asterisk.
As they inhale deeply to get every last bit of nicotine, smokers may get annoyed at rules and laws protecting others from their secondhand smoke. But passive smoke has been identified as a known cause of cancer and has been linked to heart disease, lung disorders, infections, SIDS and premature death in both children and adults.
A combination of the smoke given off by the burning tip of the cigarette, pipe or cigar and the smoke that’s exhaled, secondhand smoke includes more than 100 harmful chemical agents, and they can linger in the air for hours. While smokers get more than 100 times the dose compared to non-smokers, the U.S. Surgeon General has determined that there is no risk-free level of exposure. Even a small amount of smoke over a short period can be hazardous to health.
The most well known effects of smoking involve the lungs–cancer, emphysema, chronic bronchitis, infections and asthma.
Most Americans do not readily associate smoking with heart disease, but studies indicate that the effects of passive smoke on the cardiovascular system are particularly rapid and devastating. The American Lung Association estimates that 46,000 Americans each year die of heart disease attributed to secondhand smoke.
When Helena, Montana enacted laws forbidding smoking in public places and at work sites, hospital admissions for heart attacks declined by 40 percent. That could be taken as a coincidence were it not for the fact that when enforcement of the ban was reversed by a lawsuit, the number of heart attacks in the community once again started to rise.
As outlined in a comprehensive report published in Circulation, the journal of the American Heart Association [May 24, 2005], the cardiovascular effects of secondhand smoke are “on average, 80 percent to 90 percent as large as those from active smoking.”
The details all point to a substantial effect on the heart and blood vessels from as little as 30 minutes exposure.
Platelet Activation
The function of blood platelets is to promote clotting–very helpful in stopping the bleeding when you incur a small cut on your skin. Unwanted clotting in blood vessels near the heart, however, is a prime reason for a heart attack.
In one early study, smokers and non-smokers were exposed at the same time to 20 minutes of secondhand smoke. At baseline, smokers had elevated levels of platelet activation. At the end of the experiment, smokers had approximately the same level of platelet activation while non-smokers experienced increases until they reached nearly the same level as the smokers.
Another study found that repeated 60-minute exposures to smoke increased the baseline platelet activation of non-smokers to a level close to that of smokers.
Endothelial Function
The endothelial layer of an artery is the one in direct contact with blood; it’s crucial to healthy functioning of the blood vessels.
Abnormal function of the endothelial layer can lead to the buildup of plaque deposits (atherosclerosis) and decreased blood flow.
Environmental smoke has an immediate effect on endothelial function. With just 30 minutes of smoke exposure–comparable to that in a bar–non-smokers showed impairments comparable to those of habitual smokers. And the effect of repeated exposure was also to create endothelial dysfunction comparable to that of smokers.
On the hopeful side, at least partial recovery of endothelial function occurs after exposure to smoke ends–both in passive and active smokers.
Cholesterol
Exposure to secondhand smoke is associated with lower levels of HDL (the good cholesterol) in both adults and children. The effect on HDL is greater in males than blacks or females.
Non-smoking women exposed to smoke at work for six hours a day over a six-month period, however, had a 31 percent decrease in HDL, compared to a 33 percent decrease for smoking women in the same environment.
Inflammation
It’s now known that inflammation sets the stage for the buildup of plaque in arteries. And for both adults and children, passive smoking results in higher levels of markers for inflammation such as leukocytes, C-reactive proteins and homocysteines.
The bottom line is that less than seven hours a week of exposure to secondhand smoke increases heart attack risk by 24 percent.
Despite the changes, more than 126 million non-smokers continue to be exposed to secondhand smoke at home, in vehicles, at work or in public places.
Celebrating the first anniversary, Mercy Hospital joined other area hospitals and enacted self-imposed policies of providing for smoke-free environments, beginning January 1, 2007. Within that same year, St. Clair County enacted a law prohibiting smoking from most work environments. These measures were designed to heighten awareness and promote good health throughout the community.
If you smoke, and would like to quit, talk to your doctor about a smoking cessation plan that’s right for you.
To find a Mercy Hospital primary care physician or specialist near you, call toll-free 1 (888) MERCYME; or visit the Find a Physician Section of this website.
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