You can avoid a heart attack

Heart attack is the most common cause of death. But it is a death that more and more medical scientists feel is almost entirely preventable. Genes and increasing age play a role in heart attacks, but there are five major risk factors which can be changed: smoking, high blood pressure, elevated cholesterol, type-2 diabetes, and obesity.

"There has been a lot of research in recent years on nontraditional risk factors, but we still keep coming back to the ‘Big Five’," remarks Erika C. Jones, MD, of Cornell University in New York. "Quitting smoking, losing weight, changing the way you eat, and getting regular exercise are the most important changes you can make at any age."

Data from the Nurses Health Study suggest that, among nonsmokers, 74 percent of coronary events might be preventable by taking those steps and moderating alcoholic intake. "None of these steps are complicated. What they require is motivation for a long-term change," adds Dr. Jones.

If you’re not sure where to begin, start by checking on how well you stack up against gold standards for heart health (see table). Then focus first on any of the "big five" factors that put you at risk.

The ‘Big Five’

Some 80 to 85 percent of coronary heart disease (CHD) cases link up with at least one of the major risk factors. That’s the conclusion of a Cleveland Clinic study, which dispels the myth that as many as half of people with heart disease have no major cardiac risks (JAMA, August 20, 2003). The findings leave less room for chance or mystery factors. And they mean that your health choices count more than most people previously believed. Here’s how to choose well:

• Don’t smoke. Smoking is responsible for about one of every five cardiovascular deaths. Quitting clears this dark cloud. The smoking-related risk of developing CHD drops by half one year after a smoker kicks the habit, according to information compiled by the World Health Organization.

Newer evidence shows that among people who already have heart disease, stopping smoking can reduce mortality from all causes by 36 percent (JAMA, July 2, 2003). If you smoke, talk with a physician about aids like nicotine gum, nasal spray, and patches, combined with short-term counseling. If you’ve tried to stop before and failed, try again. It takes the average smoker three to six attempts before he succeeds.

• Control your blood pressure. Guidelines in 2003 lowered the range of "normal" blood pressure to less than 120/80 mmHg. The guidelines designate "optimal" blood pressure as 115/75 mmHg. "High blood pressure is rampant in our society," says Gary S. Francis, MD of the Cleveland Clinic. "If you live long enough, almost everyone seems to get it."

If you’re overweight, slash your systolic blood pressure (the upper number) by five to 20 points by losing 22 pounds. Shave eight to 14 points by following the DASH (Dietary Approaches to Stop Hypertension) diet. Ask your cardiologist about it. It’s low in fat and high in fruits, vegetables, whole grains, and low-fat dairy products. Take off four to nine points by exercising, with your doctor’s approval, for 30 minutes on most days of the week.

• Manage your cholesterol. Lipid abnormalities, such as high levels of LDL ("bad") cholesterol or low levels of HDL ("good") cholesterol, are well-known risk factors for coronary artery disease and heart attack. As a general rule, each one percent increase in LDL raises the risk of developing coronary artery disease by two to three percent.

The "optimal" guideline level of LDL is less than 100 mg/dL. Recent research suggests that when LDL drops well below 100, under the force of a potent statin drug, the dangerous inner wall of plaque inside heart arteries stops growing. Guidelines won’t change, though, unless and until ongoing research confirms that the low-low LDL means less CHD. But statins appear to protect the heart in other ways as well. "It’s not just the lipid-lowering that seems to benefit patients," Dr. Francis says. "It may also be the drugs’ anti-inflammatory activity. As a result, a statin would be considered even in patients with relatively normal lipid profiles but who have other cardiovascular risk factors.

You should have a fasting lipoprotein profile performed at least every five years. If abnormalities turn up, the National Cholesterol Education Program suggests "therapeutic lifestyle changes". That’s a diet low in saturated fat, high in soluble fiber and vegetables. Weight management and, again, 30 minutes of physical activity on most days of the week are the other key components of the TLC program.

• Prevent or manage diabetes. Like hypertension, type-2 diabetes is a silent disease. As a result, nearly half of people with this form of diabetes (by far the most common type) aren’t aware that they have it. Diabetes damages blood vessels throughout the body, including heart arteries.

People older than 50 should undergo a fasting plasma glucose test at least once every three years. If you have risk factors for diabetes, such as obesity or a family history of the disease, your doctor may recommend more frequent testing.

• Lose weight. If losing weight is your goal, just about any diet that helps you reduce caloric intake and closely track the food you eat will do the trick, according to a recent study from Tufts University. Researchers randomly assigned 160 overweight people to one of four popular diet plans: Weight Watchers, the low-carbohydrate Atkins diet, the very low-fat Ornish program, or the moderate-carb Zone diet – and people who stuck with any of these diets for a full year lost 10-12 pounds. The diets reduced heart disease risk by five to 15 percent.

"We prefer not to use the word ‘diet’. That implies a short-term change. These are long-term changes in the way you eat, in your lifestyle," remarks Dr. Jones.

Steer away from the drive-through fast-food lanes, Dr. Francis says, and "avoid any diets that are enormously high in fat and salt … No one is saying that you have to eat twigs and bark. But to eat fast food all the time just isn’t good for you."

Big Gains From Physical Activity

The Women’s Health Initiative observational study of 73,000 women found that those with the highest levels of physical activity cut the risk of coronary by more than 50 percent. The "dose" of aerobic exercise you need to make substantial reductions in blood pressure is modest. Just 30 minutes of aerobic physical activity, such as brisk walking, could result in a reduction of 4-9 mm Hg in blood pressure, according to National Heart, Lung and Blood Institute (NHKBI) guidelines. Not only can exercise help prevent blood pressure from rising as you age, it also helps keep arteries more flexible, allowing blood to flow more freely.

Regular aerobic exercise can lower LDL and boost HDL, even if you don’t lose weight. One small study among seven overweight or mildly obese adults at Duke University found that doing aerobic exercise four times a week for three months produced a 16-point drop in LDL cholesterol and a five-point increase in HDL.

Big Gains From Weight Loss

Losing as little as seven to 10 percent of your body weight can result in big reductions in cardiovascular risk. According to the NHLBI, if you lose just 11 extra pounds, your blood pressure could drop 2-10 mm Hg; double the weight loss to 22 pounds and you could double the benefit. A new study by the Joslin Diabetes Center found that obese adults, who lost just seven percent of their body weight by cutting 500 calories a day coupled with moderate-intensity exercise, improved major blood vessel function by approximately 80 percent over a six-month period. In many obese people and those with diabetes, the blood vessel lining loses some of its capacity to dilate, leading to both atherosclerosis and high blood pressure.

The National Diabetes Prevention Program (DPP) showed that losing seven percent of body weight, coupled with regular exercise, reduced the risk of developing type-2 diabetes by 58 percent in people at risk. "Setting unrealistic weight loss goals will only set you up for failure," asserts Dr. Jones. "The message in all these studies is that ‘modest’ weight loss is effective."

The bottom line is: Identify your major risk factors and then make up strategies to control them. Remember, heart attacks are preventable!