According to the Centers for Disease Control and Prevention (CDC), heart disease is the leading cause of death in both men and women and nearly 800,000 Americans experiencing a heart attack every year. You may already be taking steps to reduce your risk, but how do you know if you’re doing enough?
In 1948, the National Heart Institute (now known as the National Heart, Lung, and Blood Institute, or NHLBI), started the Framingham Heart Study to learn more about heart disease and stroke. The researchers followed over 5,000 participants in Framigham, Massachusetts throughout their lifetimes to determine the common risk factors for cardiovascular disease. In 1971, a second-generation group—the children of the original group and their spouses—was enrolled.
As a result of this long-term study, scientists have determined key risk factors that can increase a person’s chance of experiencing heart disease or a heart attack over their lifetime. By tracking your risk factor, you can determine how aggressive you need to be in adopting lifestyle changes and treatments.
Your risk for heart disease increases as you age, regardless of your other risk factors. According to the NHLBI, the risk increases for men after the age of 45 and for women after the age of 55 (or after menopause). The hormone estrogen is thought to help protect the heart. This is why after menopause, when estrogen levels drop in a woman’s body, her risk of heart disease also increases.
Over time, the gradual buildup of fatty plaques in the arteries can become problematic. As you get older, the arteries may narrow. Sometimes, a blood clot can form, blocking the blood flow, which can cause a heart attack.
Men are at higher risk for heart disease than women. According to the Centers for Disease Control and Prevention (CDC), 70 to 80 percent of sudden cardiac events occur in men. So far, scientists aren’t sure why this is, though studies have indicated that sex hormones may be to blame.
A study published in the journal Atherosclerosis found that two sex hormones are linked to increased levels of LDL, “bad” cholesterol and low levels of HDL, “good” cholesterol. A new study published in 2012 in The Lancet indicated that the Y chromosome, which is unique to men, may also have something to do with it. Regardless of the reason, men are at a higher risk for heart disease overall, and tend to suffer from it at an earlier age. However, heart disease is also the leading cause of death for women.
Your Total Cholesterol Levels
Your total cholesterol, which is the sum of all the cholesterol in your blood, is a potential risk factor for heart disease. This is mainly because cholesterol is a key part of the plaque that can build up in your arteries. (Plaque consists of fat, calcium, and other substances.) The theory is that the more cholesterol you have in your blood, the more may be converted into plaque buildup in your arteries. The range of cholesterol levels is:
- Normal: less than 200 mg/dL
- Borderline high: 200 to 239 mg/dL
- High: 240 mg/dL and above
The higher your total cholesterol levels, the higher your risk of heart disease.
Your HDL “Good” Cholesterol Levels
Scientists have discovered that all cholesterol is not the same. The so-called “good” cholesterol—HDL—is actually protective against heart disease. Scientists aren’t exactly sure why, but they believe that it helps to reduce inflammation, which contributes to heart health. It also helps shuttle cholesterol to the liver, where it can be processed out of the body. The general consensus is that the higher your HDL level, the lower your risk of heart disease. Generally:
- HDL lower than 40 mg/dL increases your risk of heart disease.
- HDL above 60 may offer protection against heart disease.
Your Smoking History
Overall, smoking increases your risk of heart disease. Nicotine and other chemicals in cigarettes harm the heart and blood vessels, increasing your risk of atherosclerosis (artery narrowing)—even if you smoke only once in awhile. Fortunately, no matter how much or how long you’ve smoked, quitting will benefit your heart. For example:
- Quitting reduces your risk of developing and dying from heart disease.
- Over time, quitting lowers your risk of artery narrowing.
- Quitting can help reverse heart and blood vessel damage.
Your Blood Pressure
The first number of your blood pressure reading can also give you a clue as to your risk of heart disease. This is called the “systolic” blood pressure, and measures the pressure in the arteries when the heart beats or contracts. (The diastolic number measures the pressure in the arteries between heartbeats, when the heart muscle relaxes.) The systolic measurement is considered more indicative of heart disease risk because it typically rises with age. This is due to increasing stiffness in the arteries and the long-term buildup of plaque. Here are some blood pressure guidelines:
- Normal: less than 120 mm Hg
- Prehypertension: 120 to 139 mm Hg
- High blood pressure (stage 1): 140 to 159
- High blood pressure (stage 2): 160 or higher
If you’ve already discovered that you have high blood pressure and you’re on medications to control it, you’ve automatically reduced your risk of a heart attack.
Whether or Not You Have Diabetes
Many heart disease risk calculators have added diabetes to the list. According to the National Diabetes Information Clearinghouse (NDIC), if you have diabetes, you’re at least twice as likely as someone who doesn’t have diabetes to have heart disease. Over time, high blood glucose levels (blood sugar) can increase the deposits of fatty materials in artery and blood vessel walls, increasing the chances for artery narrowing and hardening (atherosclerosis).
For a complete heart risk calculator, visit the American Heart Association. After answering a few simple questions about your blood pressure, cholesterol, and fasting blood sugar levels, for example, the site will tell you the percentage at which you’re at risk. Be sure to get regular checkups with your doctor to manage all your risk factors and keep your risk of heart disease as low as possible.