Who Is At Risk for Sudden Cardiac Arrest?

Populations Affected

Each year, between 250,000 and 450,000 Americans have sudden cardiac arrest (SCA). Ninety-five percent of these people die within minutes.

SCA occurs most often in adults in their mid-thirties to mid-forties. It affects men twice as often as women. SCA rarely occurs in children unless they have inherited problems that make them likely to have SCA. Only 1 to 2 out of every 100,000 children experiences SCA each year.

Major Risk Factors

The major risk factor for SCA is having coronary artery disease (CAD). Most people who have SCA have some degree of CAD. But most of these people don't know they have CAD until SCA occurs. Their CAD is "silent" (that is, it has no symptoms), and doctors and nurses have not previously found it. Because of this, most cases of SCA happen in people with silent CAD who have no known heart disease at the time of the event.

Many people with SCA had a silent heart attack before the SCA happened. These people have no obvious signs of having a heart attack, and they don't even realize that they've had one. The chances for having SCA are higher during the first 6 months after a heart attack.

The risk factors for developing CAD include:

• Smoking
• A family history of early cardiovascular disease (that is, heart disease diagnosed before age 55 in your father or a brother, or heart disease diagnosed before age 65 in your mother or a sister)
• High blood cholesterol
• Diabetes
• Increasing age (risk increases for men after age 45 and for women after age 55)
• High blood pressure
• Overweight and obesity
• Lack of physical activity

Other Risk Factors

Other risk factors for SCA include:

• A personal or family history of SCA
• Abnormal heart rhythms (arrhythmias)
• Birth defects of the heart or blood vessels, or an enlarged heart
• Heart failure
• Recreational drug abuse