Compared to non-smokers, smokers have two to three times the risk of developing heart disease, and an even greater risk if they have other risk factors for heart disease, such as obesity or diabetes. The Centers for Disease Control and Prevention estimates that every year, smoking causes 126,000 heart disease-related deaths. Smoking damages the heart and blood vessels in a variety of ways.
Plaque Buildup
The chemicals in cigarettes, cigars and other tobacco products harm the walls of the blood vessels, causing them to stiffen and narrow. Once blood vessels become narrowed, a fatty substance called plaque builds up on the blood vessel walls, reducing blood flow throughout the body. Smoking worsens this condition, known as atherosclerosis, and increases the risk that a person will die of cardiovascular problems, says the National Heart, Lung & Blood Institute.
Cholesterol
Smoking negatively affects cholesterol levels. Nicotine exposure lowers levels of high-density lipoprotein, or HDL or "good cholesterol," while at the same time raising low-density lipoprotein, or "bad cholesterol" levels. Smoking also elevates triglyceride levels. Too many triglycerides, a form of fat that circulates in the blood, increase the risk that a person will develop coronary artery disease, according to the American Heart Association.
Inflammation
Smoking raises inflammation levels in the body. According to research published in the journal "Public Library of Science Medicine," smokers have higher levels of the biomarkers C-reactive protein and white blood cell count. Research links these biomarkers to the development of atherosclerosis and future cardiovascular problems, such as heart attack. The more heavily a person smokes, the higher the levels of inflammation in the body.
Thicker Blood and Clots
According to the National Heart, Lung and Blood Institute, smoking thickens the blood, making it harder for your body to extract necessary oxygen. A study in the journal "Circulation" also found that compared to non-smokers, smokers had a greater risk of developing venous thromboembolism, a clotting disorder that causes clumps of blood to form in the legs or lungs.
Heart Rate and Rhythm
Smoking also contributes to increases in blood pressure and heart rate, forcing the heart to work harder and interfering with normal heart rhythms. A 2008 study published in the "American Heart Journal" found that smokers had an increased risk of atrial fibrillation, the most common type of arrhythmia in the United States. Smokers are also more likely to experience heart failure and heart attack. Heart failure is a condition where the heart cannot pump blood properly or adequately, according to the National Heart, Lung and Blood Institute.
References
- National Heart, Lung and Blood Institute: Smoking and Your Heart
- Center for Disease Control and Prevention: Annual Deaths Attributable to Cigarette Smoking, United States 2000--2004
- American Heart Association: Cigarette Smoking and Cardiovascular Diseases
- American Heart Association: Triglycerides
- Public Library of Science Medicine, Smoking and Inflammation, June 2005
