The Framingham Risk Score is used to estimate the 10-year cardiovascular risk of an individual. The Framingham Risk Score is based on data obtained from the Framingham Heart Study

Framingham Heart Study

The Framingham Heart Study is a long-term, ongoing cardiovascular study on residents of the town of Framingham, Massachusetts. The study began in 1948 with 5,209 adult subjects from Framingham, and is now on its third generation of participants...

. There are two Framingham Risk Scores, one for men and one for women.

Framingham Risk Score on the Internet

The Framingham Risk Score is available free of charge on the Internet. Everybody can estimate their 10-year cardiovascular risk on the following easy to use webpage:

http://hp2010.nhlbihin.net/atpiii/calculator.asp

Cardiovascular Risk Scoring systems

The Framingham Risk Score is one of a number of scoring systems used to determine an individual's chances of developing cardiovascular disease. This means either coronary heart disease or stroke. A number of these scoring systems are available online. Cardiovascular risk scoring systems give a best estimate of the probability that a person will develop cardiovascular disease within the next 5 or 10 years. Because they give an indication of who is most likely to develop cardiovascular disease they also indicate who is most likely to benefit from prevention. For this reason cardiovascular risk scores are used to determine who should be offered preventive drugs such as drugs to lower blood pressure and drugs to lower cholesterol levels.

Usefulness

Because the Framingham Risk Score (or another appropriate scoring system) give a good indication of the likely benefits of prevention, they are useful for both the individual patient and for the clinician in helping decide whether lifestyle modification and preventive medical treatment, and for patient education, by identifying men and women at increased risk for future cardiovascular events. The CHD risk at 10 years in percent can be calculated with the help of the Framingham Risk Score. Individuals with low risk have 10% or less CHD risk at 10 years, with intermediate risk 10-20%, and with high risk 20% or more. However it should be remembered that these categorisations are arbitrary.

A more useful metric is to consider the effects of treatment. If 100 persons have a 20% ten-year risk of cardiovascular disease it means that 20 of these 100 individuals will develop cardiovascular disease (coronary heart disease or stroke) in the next 10 years. Eighty of them will not develop cardiovascular disease in the next 10 years. If they were to take a combination of treatments (for example drugs to lower cholesterol levels plus drugs to lower blood pressure) that reduced their risk of cardiovascular disease by half it means that 10 of these 100 individuals would develop cardiovascular disease in the next 10 years: 90 of them would not develop cardiovascular disease. This means that 10 of these individuals would have avoided cardiovascular disease by taking treatment for 10 years; 10 would get cardiovascular disease whether or not they took treatment; and 80 would not have got cardiovascular disease whether or not they took treatment.

Issues Raised by Cardiovascular Risk Prediction

It is important to recognise that the strongest predictor of cardiovascular risk in any risk equation is age. Almost all persons aged 70 and over are at >20% ten year cardiovascular risk and almost nobody aged under 40 is at >20% ten year cardiovascular risk. Since those who benefit most from treatment are those at highest risk, this means that treatment of patients with raised blood pressure and raised cholesterol levels in their 30ies benefits very few. Whereas treatment of patients with "normal" blood pressure and "normal" cholesterol levels in their 70ies benefits many. This casts doubt on the wisdom of categorising individuals as having high blood pressure or raised cholesterol and treating these individual risk factors without a consideration of both their overall risk of cardiovascular disease and of the probability that they will benefit.

Background

Cardiovascular disease

Cardiovascular disease

Heart disease or cardiovascular disease are the class of diseases that involve the heart or blood vessels . While the term technically refers to any disease that affects the cardiovascular system , it is usually used to refer to those related to atherosclerosis...

 is common in the general population, affecting the majority of adults. It includes: 1) Coronary heart disease

Coronary heart disease

Coronary artery disease is the end result of the accumulation of atheromatous plaques within the walls of the coronary arteries that supply the myocardium with oxygen and nutrients. It is sometimes also called coronary heart disease...

 (CHD): Myocardial infarction

Myocardial infarction

Myocardial infarction or acute myocardial infarction , commonly known as a heart attack, results from the interruption of blood supply to a part of the heart, causing heart cells to die...

 (MI), angina pectoris, heart failure (HF), and coronary death. 2) Cerebrovascular disease

Cerebrovascular disease

Cerebrovascular disease is a group of brain dysfunctions related to disease of the blood vessels supplying the brain. Hypertension is the most important cause; it damages the blood vessel lining, endothelium, exposing the underlying collagen where platelets aggregate to initiate a repairing process...

, stroke

Stroke

A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

 and transient ischemic attack

Transient ischemic attack

A transient ischemic attack is a transient episode of neurologic dysfunction caused by ischemia – either focal brain, spinal cord or retinal – without acute infarction...

 (TIA). 3) Peripheral arterial disease, intermittent claudication

Intermittent claudication

Intermittent claudication is a clinical diagnosis given for muscle pain , classically in the calf muscle, which occurs during exercise, such as walking, and is relieved by a short period of rest.Claudication derives from the Latin verb claudicare, "to limp".-Signs:One of the hallmarks of arterial...

 and significant limb ischemia

Ischemia

In medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...

. 4) Aortic disease: Aortic atherosclerosis

Atherosclerosis

Atherosclerosis is a condition in which an artery wall thickens as a result of the accumulation of fatty materials such as cholesterol...

, thoracic aortic aneurysm

Thoracic aortic aneurysm

A thoracic aortic aneurysm is an aortic aneurysm that presents primarily in the thorax.It is less common than an abdominal aortic aneurysm. However, a syphilitic aneurysm is more likely to be a thoracic aortic aneurysm than an abdominal aortic aneurysm....

, and abdominal aortic aneurysm

Abdominal aortic aneurysm

Abdominal aortic aneurysm is a localized dilatation of the abdominal aorta exceeding the normal diameter by more than 50 percent, and is the most common form of aortic aneurysm...

.

An individual’s risk for future cardiovascular events is modifiable, by lifestyle changes and preventive medical treatment. Lifestyle changes can include stopping smoking

Smoking

Smoking is a practice in which a substance, most commonly tobacco or cannabis, is burned and the smoke is tasted or inhaled. This is primarily practised as a route of administration for recreational drug use, as combustion releases the active substances in drugs such as nicotine and makes them...

, healthy diet

Healthy diet

A healthy diet is one that helps maintain or improve general health. It is important for lowering many chronic health risks, such as obesity, heart disease, diabetes, hypertension and cancer. A healthy diet involves consuming appropriate amounts of all essential nutrients and an adequate amount of...

, regular exercise, etc. Preventive medical treatment can include a statin

Statin

Statins are a class of drugs used to lower cholesterol levels by inhibiting the enzyme HMG-CoA reductase, which plays a central role in the production of cholesterol in the liver. Increased cholesterol levels have been associated with cardiovascular diseases, and statins are therefore used in the...

, mini dose aspirin

Aspirin

Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...

, treatment for hypertension

Hypertension

Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...

, etc. It is important to be able to predict the risk of an individual patient, in order to decide when to initiate lifestyle modification and preventive medical treatment.

Multiple risk models for the prediction of cardiovascular risk of individual patients have been developed. One such key risk model is the Framingham Risk Score.

The Framingham Risk Score is based on findings from the Framingham Heart Study

Framingham Heart Study

The Framingham Heart Study is a long-term, ongoing cardiovascular study on residents of the town of Framingham, Massachusetts. The study began in 1948 with 5,209 adult subjects from Framingham, and is now on its third generation of participants...

.

Validation

The Framingham Risk Score has been validated in the USA, both in men and women, both in European Americans and African Americans.. While several studies have claimed to improve on the FRS, there is little evidence for any improved prediction beyond the Framingham risk score

Limitations

There are two limitations.

The Framingham Risk Score predicts only future coronary heart disease (CHD) events. It does not predict future total cardiovascular events, i.e. it does not also predict risk for stroke, transient ischemic attack (TIA), and heart failure. These also important patient outcomes were included in the 2008 Framingham General Cardiovascular Risk Score. The predicted risk for an individual usually is higher with the 2008 Framingham General Cardiovascular Risk Score than with the 2002 Framingham Risk Score.

The Framingham Risk Score could overestimate or underestimate risk in populations other than the US population , and within the USA in populations other than European Americans and African Americans, e.g. Hispanic Americans and Native Americans. It is not yet clear if this limitation is real, or appears to be real because of differences in methodology, etc. As a result, other countries may prefer to use another risk score, e.g. SCORE, which has been recommended by the European Society of Cardiology

European Society of Cardiology

The European Society of Cardiology is a membership organisation of more than 70,000 cardiology professionals across Europe and the Mediterranean. It is involved in scientific and educational activities for cardiology professionals and also promotes cardiovascular disease prevention messages to the...

 in 2007.

If possible, a cardiology

Cardiology

Cardiology is a medical specialty dealing with disorders of the heart . The field includes diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology...

 professional should select the risk prediction model which is most appropriate for an individual patient.

Current version of the Framingham Risk Score

The current version of the Framingham Risk Score was published in 2002. The publishing body is the ATP III, i.e. the «Adult Treatment Panel III», an expert panel of the National Heart, Lung, and Blood Institute

National Heart, Lung, and Blood Institute

The National Heart, Lung, and Blood Institute is a division of the National Institutes of Health, located in Bethesda, Maryland...

, which is part of the National Institutes of Health

National Institutes of Health

The National Institutes of Health are an agency of the United States Department of Health and Human Services and are the primary agency of the United States government responsible for biomedical and health-related research. Its science and engineering counterpart is the National Science Foundation...

 (NIH), USA.

The original Framingham Risk Score had been published in 1998.

Differences between the versions

The first Framingham Risk Score included age, gender, LDL cholesterol, HDL cholesterol, blood pressure (and also whether the patient is treated or not for his/her hypertension), diabetes, and smoking. It estimated the 10-year risk for coronary heart disease (CHD). It performed well, and correctly predicted 10-year risk for CHD in American men and women of European and African descent.

The updated version was modified in dyslipidaemia, age range, hypertension treatment, smoking, and total cholesterol, and it excluded diabetes, because diabetes meanwhile was considered to be a CHD Risk Equivalent.

CHD Risk Equivalent

Some patients without known CHD have risk of cardiovascular events that is comparable to that of patients with established CHD. Cardiology professionals refer to such patients as having a CHD Risk Equivalent. These patients should be managed as patients with known CHD. Diabetes is accepted as a CHD Risk Equivalent.

Analysis of the US population with the Framingham/ATP III criteria

The Framingham/ATP III criteria were used to estimate CHD risk in the USA. Data from 11,611 patients from a very large study, the NHANES III, were used. The patients were 20 to 79 years of age, and had no self reported CHD, stroke, peripheral arterial disease, or diabetes.

The results: 82% of patients had low risk (10% or less CHD risk at 10 years). 16% had intermediate risk (10-20%). 3% had high risk (20% or more).

High risk was most commonly found in patients with advanced age, and was more common in men than women.

No fully standardised name

Framingham Risk Score: The first part of this name, i.e. "Framingham", may be called either "Framingham" or "Framingham/ATP III" by cardiology professionals, and the second part may be called "Score", "Risk Score" or "Cardiac Risk Score". All possible combinations have been used. However, "Framingham Risk Score" is more common than the other variants.

The Framingham Risk Score in detail

Below are the points of the Framingham Risk Score in detail. However, it is much easier to use the calculator on the Internet.

Framingham Risk Score for Women

Age: 20-34 years: Minus 7 points. 35-39 years: Minus 3 points. 40-44 years: 0 points. 45-49 years: 3 points. 50-54 years: 6 points. 55-59 years: 8 points. 60-64 years: 10 points. 65-69 years: 12 points. 70-74 years: 14 points. 75-79 years: 16 points.

Total cholesterol, mg/dL: Age 20-39 years: Under 160: 0 points. 160-199: 4 points. 200-239: 8 points. 240-279: 11 points. 280 or higher: 13 points. • Age 40-49 years: Under 160: 0 points. 160-199: 3 points. 200-239: 6 points. 240-279: 8 points. 280 or higher: 10 points. • Age 50-59 years: Under 160: 0 points. 160-199: 2 points. 200-239: 4 points. 240-279: 5 points. 280 or higher: 7 points. • Age 60-69 years: Under 160: 0 points. 160-199: 1 point. 200-239: 2 points. 240-279: 3 points. 280 or higher: 4 points. • Age 70-79 years: Under 160: 0 points. 160-199: 1 point. 200-239: 1 point. 240-279: 2 points. 280 or higher: 2 points.

If cigarette smoker: Age 20-39 years: 9 points. • Age 40-49 years: 7 points. • Age 50-59 years: 4 points. • Age 60-69 years: 2 points. • Age 70-79 years: 1 point.

All non smokers: 0 points.

HDL cholesterol, mg/dL: 60 or higher: Minus 1 point. 50-59: 0 points. 40-49: 1 point. Under 40: 2 points.

Systolic blood pressure, mm Hg: Untreated: Under 120: 0 points. 120-129: 1 point. 130-139: 2 points. 140-159: 3 points. 160 or higher: 4 points. • Treated: Under 120: 0 points. 120-129: 3 points. 130-139: 4 points. 140-159: 5 points. 160 or higher: 6 points.

10-year risk in %: Points total: Under 9 points: <1%. 9-12 points: 1%. 13-14 points: 2%. 15 points: 3%. 16 points: 4%. 17 points: 5%. 18 points: 6%. 19 points: 8%. 20 points: 11%. 21=14%, 22=17%, 23=22%, 24=27%, 25=30%

Framingham Risk Score for Men

Age: 20-34 years: Minus 9 points. 35-39 years: Minus 4 points. 40-44 years: 0 points. 45-49 years: 3 points. 50-54 years: 6 points. 55-59 years: 8 points. 60-64 years: 10 points. 65-69 years: 11 points. 70-74 years: 12 points. 75-79 years: 13 points.

Total cholesterol, mg/dL: Age 20-39 years: Under 160: 0 points. 160-199: 4 points. 200-239: 7 points. 240-279: 9 points. 280 or higher: 11 points. • Age 40-49 years: Under 160: 0 points. 160-199: 3 points. 200-239: 5 points. 240-279: 6 points. 280 or higher: 8 points. • Age 50-59 years: Under 160: 0 points. 160-199: 2 points. 200-239: 3 points. 240-279: 4 points. 280 or higher: 5 points. • Age 60-69 years: Under 160: 0 points. 160-199: 1 point. 200-239: 1 point. 240-279: 2 points. 280 or higher: 3 points. • Age 70-79 years: Under 160: 0 points. 160-199: 0 points. 200-239: 0 points. 240-279: 1 point. 280 or higher: 1 point.

If cigarette smoker: Age 20-39 years: 8 points. • Age 40-49 years: 5 points. • Age 50-59 years: 3 points. • Age 60-69 years: 1 point. • Age 70-79 years: 1 point.

All non smokers: 0 points.

HDL cholesterol, mg/dL: 60 or higher: Minus 1 point. 50-59: 0 points. 40-49: 1 point. Under 40: 2 points.

Systolic blood pressure, mm Hg: Untreated: Under 120: 0 points. 120-129: 0 points. 130-139: 1 point. 140-159: 1 point. 160 or higher: 2 points. • Treated: Under 120: 0 points. 120-129: 1 point. 130-139: 2 points. 140-159: 2 points. 160 or higher: 3 points.

10-year risk in %: Points total: 1 point: 6%. 2 points: 8%. 3 points: 10%. 4 points: 12%. 5 points: 16%. 6 points: 20%. 7 points: 25%. 10 points or more: Over 30%.

Further risk score profiles based on the Framingham Heart Study

Not only coronary heart disease (CHD) events, but also further risks can be predicted. Risk prediction models for cardiovascular disease outcomes other than CHD events have also been developed by the Framingham Heart Study researchers. Amongst others, a risk score for 10-year risk for atrial fibrillation

Atrial fibrillation

Atrial fibrillation is the most common cardiac arrhythmia . It is a common cause of irregular heart beat, identified clinically by taking a pulse. Chaotic electrical activity in the two upper chambers of the heart result in the muscle fibrillating , instead of achieving coordinated contraction...

has been developed.

A calculator for 10-year risk for atrial fibrillation is available free of charge on the official website of the Framingham Heart Study:

http://www.framinghamheartstudy.org/risk/atrial.html#