We've all been told how important it is to control major risk factors for heart attack and coronary artery disease. We know, for example, not to smoke...to maintain LDL (bad) cholesterol at safe levels...raise HDL (good) cholesterol as high as possible. keep blood pressure below 120/80...and monitor our blood levels of C-reactive protein and homocysteine—a protein and amino acid that, when elevated, indicate increased heart attack risk.

What you may not know: Cardiovascular risk factors are synergistic, so any one of the risk factors mentioned above increases the effect of other risk factors.

Example: Even slightly elevated cholesterol or blood pressure becomes more dangerous in the presence of smaller, lesser-known risk factors such as...

  • Steroid medications. Most people now know that nonsteroidal anti-inflammatory drugs, including the prescription medication celecoxib (Celebrex) and over-the-counter products such as ibuprofen (Advil) and naproxen (Aleve), increase heart attack and stroke risk by making blood platelets sticky. However, steroid drugs are perhaps the most dangerous of the "stealth" risk factors for heart attack.

Steroids, which include cortisone, prednisone and prednisolone Orapred), are prescribed for inflammatory conditions such as colitis, inflammatory bowel disease, psoriasis, asthma and rheumatoid arthritis.

Besides raising cholesterol levels and blood pressure slightly, steroids also tend to promote the entry of cholesterol into the artery wall to form atherosclerotic plaque deposits.

Important: Only oral and injectable forms of steroid medications carry these risks—the inhaled form used to treat asthma does not.

Taking steroid medications also raises risk for atrial fibrillation, an irregular heartbeat associated with increased risk for stroke.

Self-defense: Avoid using oral and injectable steroids if at all possible. If you must use them, make sure your cholesterol levels and blood pressure are well-managed...take the lowest possible dose...and, whenever possible, avoid using them for more than a week or two.

Important: Abrupt discontinuation of steroids, without gradually tapering off, may cause serious side effects. Always consult your physician before stopping a steroid medication.

  • Stress. Both chronic and acute stress can be hard on the heart—but in slightly different ways.

Chronic stress, such as from ongoing financial pressures or a strained relationship, raises blood levels of the stress hormones epinephrine (adrenaline), norepinephrine and cortisol, accelerating buildup of dangerous plaque in the coronary arteries much as steroid drugs do.

Self-defense: Address the underlying cause of the chronic stress...engage in daily aerobic exercise, which burns off excess epinephrine in the bloodstream and reduces anxiety...and practice stress-reduction techniques, such as biofeedback and meditation, which have been shown to lower epinephrine and norepinephrine levels.

Acute stress, such as from the sudden death of a spouse, not only increases stress hormones but also causes the coronary arteries to constrict. In addition, acute stress increases the heart's need for, and consumption of oxygen. If you already have a partially blocked coronary artery due to plaque buildup, this constriction and increased oxygen consumption can contribute to a dangerous shortage of blood flow to the heart.

Self-defense: If you are confronted with acute or chronic stress, ask your doctor to consider prescribing a beta-blocker, such as propranolol (Inderal), atenolol (Tenormin) or metoprolol (Lopressor). These drugs are typically used to treat heart conditions and high blood pressure. However, beta-blockers also protect against the harmful arterial effect that occurs with stress and can be taken as long as stress-related symptoms occur. These drugs are not recommended for those with low blood pressure, asthma or abnormally low heart rate.

  • Sleep apnea. People who suffer from this condition stop breathing during their sleep for a few seconds at a time many times per night. Sleep apnea not only disrupts sleep but also is associated with an increased risk for heart attack and heart disease.

Self-defense: Half of people with mild sleep apnea (those who stop breathing five to 15 times per hour) and 20% of those with moderate apnea (15 to 30 breathing stoppages per hour) have so-called positional sleep apnea-that is, the disturbed breathing occurs only when the person is sleeping on his/her back.

Good solution: A relatively new strap-on foam device called Zzoma, which forces you to lie on your side, appears to help prevent positional sleep apnea (available for $189.95 from the manufacturer at 877-799-9662 or www.zzomasleep.com).

For more serious cases, continuous positive airway pressure (CPAP), a type of therapy in which the sleeper wears a mask that blows air into his nostrils, helps reduce apnea symptoms. For those who find the CPAP mask uncomfortable, oral appliances, prescribed by dentists, also help reduce apnea symptoms.

  • Anemia. With this condition, the blood's ability to carry oxygen is impaired. This can trigger chest pain (angina) or even a heart attack in people whose coronary arteries are partially blocked. Always seek immediate medical attention if you have chest pain.

Self-defense: Anemia often can be treated with iron, vitamin B-12 or folic acid supplements or medications. After you've sought medical attention for chest pain, be sure that your physician tests you for anemia.

  • Chlamydia infection. Chlamydia pneumoniae is a bacterium found in the respiratory tract of more than two million Americans. Different from the germ that causes the sexually transmitted disease chlamydia, C. pneumoniae is associated with increased risk for coronary artery disease, possibly because it contributes to arterial inflammation.

Self-defense: If you have signs of a respiratory infection, your doctor may want to order a blood test for C. pneumoniae. Antibiotics can effectively treat an infection caused by this bacterium.

  • Vitamin K deficiency. Vitamin K (found mostly in meats, cheeses and leafy green vegetables) has been shown to reduce cardiovascular risk in people by more than 50% and also has prevented hardening of the arteries in animal studies. Vitamin K is also produced by the bacteria naturally residing in the intestine. Researchers have found, however, that most people don't get enough vitamin K in their diets.

Self-defense: To ensure that you get enough of this crucial vitamin, ask your doctor about taking a high-dose vitamin K supplement (100 micrograms daily for adults). Because vitamin K can reduce the effects of blood-thinning medication, it is never recommended for people taking warfarin (Coumadin) or other blood thinners.

  • Horizontal earlobe creases. Though no one knows why, some research has shown that people who have a horizontal crease in one or both of their earlobes may be at increased risk for coronary artery disease.

Self-defense: While there's nothing that can be done to change this risk factor, anyone with such creases should be especially careful about monitoring other cardiovascular risk factors.

Heart Attacks Increase In the Cold

Researchers analyzed 84,010 hospital admissions for heart attacks over four years.

Result: For every half-degree drop in temperature, relative risk for heart attack increased by 2%. Adults ages 75 to 84 were especially vulnerable.

Theory: Cold temperatures may increase blood pressure, blood thickness and the heart's workload.

Self-defense: In winter, bundle up when going outdoors and closely monitor other heart attack risk factors, including stress and body weight.

Don't Make Your Heart Work Overtime

People who regularly worked three or more hours beyond a standard eight-hour day had a 60% higher risk for heart-related problems, including fatal heart attacks and angina, than people who maintained regular hours.

Possible reason: People who frequently work long hours tend to be type A personalities-aggressive, competitive and tense. This can make them more susceptible to heart disease, although researchers are not yet sure why. It may be related to unhealthy lifestyles and high stress levels.

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