Smoking is, quite simply, hard on the heart. One of the major risk factors for coronary artery disease, also called CAD, smoking attacks both the heart and blood leading to increased risks of heart disease. According to the National Heart Lung and Blood Institute, smoking impacts your heart health in several ways:
• Lowers levels of “good” or high-density lipoprotein levels
• Raises levels of “bad” or low-density lipoprotein levels
• Raises blood pressure causing heart to work harder
• Thickens blood which restricts the ability to deliver oxygen
• Damages blood vessels leaving them “stiff and less elastic”
• Contributes to atherosclerosis by causing plaques to form due to inflammation
Compared to their non-smoking counterparts, smokers are two to three times more likely to develop heart disease, have double the risk of suffering a heart attack, and are more likely to die from some form of heart disease, including heart attack or heart failure. (NHLBI 2.)
The impact of smoking, as well as second hand smoke, becomes even more damaging and dangerous for women who are pregnant and their unborn child. Smoking has been linked to various pregnancy related conditions such as placental abruption, ectopic pregnancy, vaginal bleeding, placenta previa, and stillbirths. When a pregnant mother is exposed to smoke, it’s more common for the baby to be born prematurely or to have a low birth weight. Smoke exposure in babies has also been linked to birth defects. Secondhand smoke is also linked to sudden infant death syndrome, ear infections, and lung conditions such as asthma or bronchitis. (MoD 1.)
While the link between smoking and babies with low birth weight, SIDS, and lung conditions is well established and generally accepted, what has not been known until now is whether or not exposure to smoke, either during pregnancy or second hand smoke after birth, has the same impact to heart health in infants and children as it does in adults. Australian researchers, led by David Celermajer, Scandrett Professor of Cardiology at the University of Sydney, believe that smoking during pregnancy increases a child’s risk of developing cardiovascular disease later in life.
As a part of the study, Celermajer and his team measured the lipoprotein levels and arterial wall thickness in a group of 405 children. All children were 8 years old at the time of testing, and born between 1997 and 1999. Each received an ultrasound to measure changes in the arterial wall but only 328 children consented to blood testing for lipoprotein levels. The participants were also part of a study since birth investigating asthma and allergies.
Researchers found that children whose mothers smoked during pregnancy had lower than normal levels of high-density lipoprotein, or good cholesterol, compared to children of non-smoking mothers. It’s generally accepted that low levels of HDL cholesterol increase the risk of heart disease. In addition, researchers believe that evidence indicatede the main culprit in lower HDL cholesterol levels was due to smoking during pregnancy and other factors such as second hand smoke. Celermajer estimated that the findings indicated that the low HDL levels equates to a 10-15 percent increased risk of heart disease later in life. Celermajer recommended at-risk children be monitored long term for risk factors for heart disease.
European Society of Cardiology (2011, June 21). Smoking during pregnancy lowers levels of 'good' HDL cholesterol in children. ScienceDaily. Retrieved June 22, 2011, from http://www.sciencedaily.com/releases/2011/06/110621182959.htm
What are the Risks of Smoking?, National Heart Lung and Blood Institute, http://www.nhlbi.nih.gov/health/dci/Diseases/smo/smo_risks.html
Alcohol and Drugs: Smoking during pregnancy, March of Dimes, April 2010, April 2010
Reviewed June 23, 2011
Edited by Alison Stanton