Heart attack risk assessment tools

Related Terms

Abdominal fat, coronary heart disease, diabetes, diabetes mellitus, heart attack, heart disease, high blood pressure, high cholesterol, hip to waist ratio, hypertension, obesity, risk assessment tool, stroke, triglycerides.

Background

Many important factors can impact a person's risk of having a heart attack within 10 years. The most important risk factors include high blood pressure, high cholesterol, smoking, diabetes, inactivity, or being overweight or obese. Some risk factors, including gender, age, and heredity, cannot be controlled. The more risk factors a person has, the greater his/her risk of developing heart disease or having a heart attack.
Several organizations, including the American Heart Association, have designed online calculators, or risk assessment tools, to help people estimate their risks of having heart attacks. These calculators are designed for people who are older than 20 years of age who do not already have heart disease.
These tools, which are available online, also help individuals determine if they may have metabolic syndrome, which is a group of medical conditions that greatly increases a person's chance of developing heart disease. Indicators of metabolic syndrome include a large waist circumference (also called abdominal obesity), high blood pressure, high blood sugar levels, and high cholesterol levels.
These risk assessment tools vary slightly in their methodology. In general, these tools are based on the results of a research study, called the Framingham Heart Study, and the National Cholesterol Education Program (NCEP)'s Adult Treatment Panel (ATP) III Guidelines. This longitudinal study and written report have identified important risk factors for heart disease.
The American Heart Association recommends that all individuals who are 40 years of age or older check their risks every five years. Some people are encouraged to use this tool at an earlier age. For instance, if a person's immediate family member had heart disease at an early age (mother or sister diagnosed before the age of 65 or father or brother diagnosed before the age of 55), it is recommended that he/she knows his/her risk factors before the age of 20.
Heart attack risk assessment tools should not replace regular visits to the doctor. They are meant to be used in addition to regular medical checkups.
These tools are also not recommended for people who have already been diagnosed with heart disease, diabetes, peripheral arterial disease, abdominal aortic aneurysm, or carotid artery disease. These people already have a 20% increased risk of having a heart attack or coronary heart disease in the next 10 years. These people should talk to their doctors and cardiologists about their health risks.

Theory / Evidence

General: Most risk assessment tools use scoring systems from the Framingham Heart Study and the Adult Treatment Panel (ATP) III Guidelines to assess a person's risk of having a heart attack or developing metabolic syndrome or heart disease.
The Framingham Heart Study, which began in 1948 and involved more than 5,000 participants, aimed to determine important risk factors for heart disease. Much of what researchers currently know about heart disease, including the effects of diet, weight, gender, and smoking, is based on this study. Researchers from the Framingham Heart study are currently evaluating a third generation of participants to learn more about why certain people get heart disease and how people can decrease their risks of developing heart disease.
The National Cholesterol Education Program (NCEP) wrote the ATP III Guidelines, which provides information on how to prevent, detect, evaluate, and treat high cholesterol in adults. These evidence-based guidelines take into consideration many factors, including a person's age, family history, gender, and ethnicity. ATP III is endorsed by the American Heart Association and is sponsored by the National Heart, Lung, and Blood Institute (NHLBI).
According to the Framingham Heart Study and ATP III Guidelines, the main factors that increase a person's risk of heart attack include high blood cholesterol, diabetes mellitus, high blood pressure, smoking, male gender, family history, age, previous history, and obesity.
Age: The risk of having a heart attack appears to increase with age. About 83% of people who die from heart disease are 65 years of age or older. Age also increases the chances that a heart attack will be fatal. According to the American Heart Association (AHA), 80% of people who die from heart attacks are older than 65 years of age.
Diabetes mellitus: Individuals with diabetes have a substantially greater risk of a heart attack. This is because diabetes may damage arteries, predisposing diabetics to atherosclerosis (hardening of the arteries). Overall, the risk of heart disease is two-and-a-half times higher in men and women with diabetes compared to people without diabetes.
Family history: A family history of heart disease increases a person's risk of a heart attack. This is because many risk factors for heart disease, such as high blood pressure, high cholesterol, and obesity, may be related to a person's biological makeup.
High blood cholesterol: Cholesterol is a major component of atherosclerotic plaque, which consists of particles of blood, cholesterol, and protein that clump together and lead to blocked arteries in the heart. These blockages may result in a heart attack. An elevated level of total cholesterol is associated with an increased risk of coronary atherosclerosis (hardening of the arteries) and heart attack. Total cholesterol levels should be below 200 milligrams per deciliter of blood.
Elevated levels of low-density lipoprotein (LDL or "bad cholesterol") are also associated with an increased incidence of both atherosclerosis and heart attack.
Low levels of high-density lipoprotein (HDL or "good cholesterol") have also been associated with an increased risk of atherosclerosis and heart attack. HDL levels of 60 milligrams per deciliter of blood or more may help to lower the risk for developing heart disease.
Eating a diet high in cholesterol increases a person's risk of developing high blood pressure. Other factors, such as obesity, age, male gender, smoking, high blood pressure, and diabetes, may increase a person's risk of developing high cholesterol. People with family histories of high cholesterol may be predisposed to developing high cholesterol as well.
High blood pressure: High blood pressure, or hypertension, has consistently been associated with an increased risk of heart attack. This is because high blood pressure may weaken and damage blood vessels in and around the heart, making them vulnerable to atherosclerosis (hardening of the arteries) and bleeding.
Inactivity: People who do not exercise regularly have an increased risk of having a heart attack. Inactivity has been linked to high blood pressure, heart disease, stroke, and diabetes. The American Heart Association (AHA) recommends that people engage in moderate exercise (50-80% aerobic capacity) for 30-60 minutes at least three to four days per week.
Male gender: The incidence of heart attack is higher in men than women in all age groups. This gender difference in heart attack incidence, however, narrows with increasing age. Risks for heart attack increase in men older than 45 years of age and women older than 55 years of age. The natural estrogen produced by the body protects women from heart disease before menopause. As levels of estrogen decline, the incidence of heart disease increases.
Obesity: Being overweight or obese (a body mass index that is greater than 25) increases the chances of developing high blood pressure, heart disease, atherosclerosis (hardening of the arteries), and diabetes, all of which increase the risk of having a heart attack. Having excess abdominal fat (hip to waist ratio higher than 0.8 in women and higher than 1.0 in men) has also been shown to increase a person's risk of heart disease and heart attack.
Previous history: Having a history of a previous heart attack increases the risk of having another heart attack. This is because part of the heart becomes permanently damaged or scarred after a heart attack. People who have had heart surgery, such as angioplasty, also have an increased risk of having a heart attack because their hearts and/or arteries are already damaged from heart disease. In addition, people that have histories of angina (chest pain) are more likely to have a heart attack. This is because angina is often a symptom of coronary artery disease (CAD), a condition that may lead to a heart attack.
Smoking: Certain chemicals present in tobacco, or that are inhaled after lighting tobacco, are known to damage blood vessel walls. Smoking contributes to plaque buildup in the arteries. Nicotine, found in cigarettes, makes the heart work harder by increasing heart rate and blood pressure. The carbon monoxide in cigarette smoke replaces oxygen in the blood, decreasing the amount of oxygen delivered to the heart and the rest of the body.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

Bibliography

American Heart Association (AHA). .
Boden WE. Therapeutic implications of recent ATP III guidelines and the important role of combination therapy in total dyslipidemia management. Curr Opin Cardiol. 2003 Jul;18(4):278-85.
Gotto AM, NCEP ATP III. NCEP ATP III guidelines incorporate global risk assessment. Am J Manag Care. 2003 Aug;Suppl:1, 3.
Kelly-Hayes M, Beiser A, Kase CS, et al. The influence of gender and age on disability following ischemic stroke: the Framingham study. J Stroke Cerebrovasc Dis. 2003 May-Jun;12(3):119-26.
Larson MG, Atwood LD, Benjamin EJ, et al. Framingham Heart Study 100K project: genome-wide associations for cardiovascular disease outcomes. BMC Med Genet. 2007 Sep 19;8 Suppl 1:S5.
Levy D, Larson MG, Benjamin EJ, et al. Framingham Heart Study 100K Project: genome-wide associations for blood pressure and arterial stiffness. BMC Med Genet. 2007 Sep 19;8 Suppl 1:S3.
National Heart, Lung, and Blood Institute (NHLBI). .
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Technique

In order to use a heart attack risk assessment tool, individuals need to know information about their health. Most calculators ask people to enter their age, gender, height, and weight. Many calculators also ask people to enter their blood pressure, cholesterol levels (total, LDL, HDL, and triglycerides), and blood sugar levels. Individuals can ask their doctors for these test results if they do not know what they are. In order to get accurate results, it is important that individuals enter in their own, up-to-date information.
Most risk assessment tools use scoring systems based on the Framingham Heart Study and the Adult Treatment Panel (ATP) III Guidelines to assess a person's risk of having a heart attack or developing metabolic syndrome or heart disease.
After the person enters in his/her medical information, the risk assessment tool provides the person's estimated risk of experiencing a heart attack in the next 10 years. The more risk factors a person has, the greater his/her risk of developing heart disease or having a heart attack. It is important to note that this is just an estimate. If a person's risk is low it does not guarantee he/she will not have a heart attack. Likewise, if a person's risk is high, it does not necessarily mean he/she will have a heart attack.
Based on the person's responses, the risk assessment tool provides suggestions on how to lower his/her risk of having a heart attack. For instance, weight and smoking are heart attack risk factors that a person can control. If a person has a high risk of having a heart attack because he/she is overweight and smokes, the calculator provides information on how to lose weight and stop smoking. It is important to note that some risk factors, including gender, age, and heredity, cannot be controlled.
People with high risks of having heart attacks and heart disease are encouraged to visit their doctors. After a thorough physical examination, a doctor may be able to provide more information on how to maintain a healthy heart.