Framingham Risk Score

Framingham Risk Score is a scoring system used to assess an individual’s risk of developing cardiovascular disease over the next 10-years. It was first developed from the Framingham Heart Study in 1948 on residents of the town of Framingham, United States under the direction of the National Heart, Lung and Blood Institute (NHLBI) and is now on its third generation of participants. It is gender-specific algorithm; scoring system is different for men and women. It is practical, clinically relevant and modestly accurate but its effectiveness seems somewhat limited in certain specific populations.

Variables of Framingham Risk Score:

Six variables are used in Framingham Risk Score for assessment of cardiovascular risk:

1. Age of person

2. Diabetes

3. Smoking status

4. Total cholesterol – Total cholesterol is the sum of all cholesterol in our blood. Practically, it is estimated by summation of HDL cholesterol, LDL cholesterol and one fifth of triglyceride. Its optimal level is less than 200 mg/dl. The higher the level, the greater the risk for cardiovascular disease.

5. HDL (high density lipoprotein) cholesterol – This cholesterol is beneficial for us. High density lipoprotein carries excess cholesterol from the peripheral tissues to the liver for disposal from the body via bile. Its optimal level is 60 mg/dl or more that is considered as a protective against cardiovascular disease. Level less than 40 mg/dl greatly increase the risk of developing cardiovascular disease.

6. Systolic blood pressure – It is the first portion of blood pressure recording. For example, if a person’s recording is 130/80 mg Hg, the systolic blood pressure is 130 mg Hg.

Framingham Risk Score for men:

 

(I). Estimation of points:

 

1. Age of person:

Age Points
30 – 34 0
35 – 39 2
40 – 44 5
45 – 49 6
50 – 54 8
55 – 59 10
60 – 64 11
65 – 69 12
70 – 74 14
75 or more 15

 

2. Diabetes:

Diabetes Points
Absent 0
Present 3

 

3. Smoking status:

Smoking status Points
Non-smoker 0
Smoker 4

 

4. Serum total cholesterol:

Serum total cholesterol (mg/dl) Points
Less than 160 0
160 – 199 1
200 – 239 2
240 – 279 3
280 or more 4

 

5. Serum HDL (high density lipoprotein) cholesterol:

Serum HDL cholesterol (mg/dl) Points
60 or more -2
50 – 59 -1
45 – 49 0
35 – 44 1
Less than 35 2

 

6. Systolic blood pressure not treated:

Systolic blood pressure (mg Hg) Points
Less than 120 -2
120 – 129 0
130 – 139 1
140 – 159 2
160 or more 3

 

7. Systolic blood pressure treated:

Systolic blood pressure (mg Hg) Points
Less than 120 0
120 – 129 2
130 – 139 3
140 – 159 4
160 or more 5

 

(II). Assessment of cardiovascular risk according to total points of Framingham Risk Score:

 

Points 10 years cardiovascular risk in %
-3 or less <1
-2 1.1
-1 1.4
0 1.6
1 1.9
2 2.3
3 2.8
4 3.3
5 3.9
6 4.7
7 5.6
8 6.7
9 7.9
10 9.4
11 11.2
12 13.2
13 15.6
14 18.4
15 21.6
16 25.3
17 29.4
18 or more >30

 

(III). Risk categorization:

Risk groups Points Cardiovascular risk over the next 10-years
Low risk Less than 11 Less than 10%
Intermediate risk 11 – 14 10 – 20%
High risk 15 or more More than 20%
(IV). Example:

A male person is 60 years of age, diabetic, smoker, his serum total cholesterol is 190 mg/dl and HDL cholesterol is 45 mg/dl, has blood pressure 120 mg Hg with drug treatment. His Framingham Risk Score would be 11 + 3 + 4 + 1 + 0 + 1 = 20. He is a high risk individual and has a more than 30% risk of developing cardiovascular disease such as myocardial infarction over the next 10 years.

Framingham Risk Score for women:

 

(I). Estimation of points:

 

1. Age of person:

Age Points
30 – 34 0
35 – 39 2
40 – 44 4
45 – 49 5
50 – 54 7
55 – 59 8
60 – 64 9
65 – 69 10
70 – 74 11
75 or more 12

 

2. Diabetes:

Diabetes Points
Absent 0
Present 4

 

3. Smoking status:

Smoking status Points
Non-smoker 0
Smoker 3

 

4. Serum total cholesterol:

Serum total cholesterol (mg/dl) Points
Less than 160 0
160 – 199 1
200 – 239 3
240 – 279 4
280 or more 5

 

5. Serum HDL (high density lipoprotein) cholesterol:

Serum HDL cholesterol (mg/dl) Points
60 or more -2
50 – 59 -1
45 – 49 0
35 – 44 1
Less than 35 2

 

6. Systolic blood pressure not treated:

Systolic blood pressure (mg Hg) Points
Less than 120 -3
120 – 129 0
130 – 139 1
140 – 149 2
150 – 159 4
160 or more 5

 

7. Systolic blood pressure treated:

Systolic blood pressure (mg Hg) Points
Less than 120 -1
120 – 129 2
130 – 139 3
140 – 149 5
150 – 159 6
160 or more 7

 

(II). Assessment of cardiovascular risk according to total points of Framingham Risk Score:

 

Points 10 years cardiovascular risk in %
-2 or less <1
-1 1
0 1.2
1 1.5
2 1.7
3 2
4 2.4
5 2.8
6 3.3
7 3.9
8 4.5
9 5.3
10 6.3
11 7.3
12 8.6
13 10.0
14 11.7
15 13.7
16 15.9
17 18.5
18 21.5
19 24.8
20 28.5
21 or more >30

 

(III). Risk categorization:
Risk groups Points Cardiovascular risk over the next 10-years
Low risk Less than 13 Less than 10%
Intermediate risk 13 – 17 10 – 20%
High risk 18 or more More than 20%
(IV). Example:

A female person is 65 years of age, diabetic, non-smoker, her serum total cholesterol is 220 mg/dl and HDL cholesterol is 40 mg/dl, has blood pressure 130 mg Hg without any treatment. Her Framingham Risk Score would be 10 + 4 + 0 + 3 + 1 + 1 = 19. She is a high risk individual and has a 24.8% risk of developing cardiovascular disease such as myocardial infarction over the next 10 years.

Benefit of Framingham Risk Score:

Framingham Risk Score not only estimate the cardiovascular risk but also guide for prevention of cardiovascular disease. Prevention can be achieved by modification of lifestyle and initiating the preventive drug therapy. It is important to be able to decide when to initiate lifestyle modification and preventive drug therapy.

Usually individuals with low to intermediate risk are recommended for lifestyle modification. Lifestyle modification including avoid cigarette smoking, perform regular exercise (minimum of 20 minutes, three times per week), intake healthy diet that contains less amount of saturated fat and rich in fresh fruits and vegetables, maintain an ideal body weight, and reduce alcohol consumption. Individuals with intermediate risk should monitor their risk profile every 6–12 months.

High risk individuals are recommended for both lifestyle modification and preventive drug therapy. Preventive drug therapy including statin intake to control cholesterol level, low dose aspirin to prevent thromboembolic manifestations, treatment for diabetes and treatment for high blood pressure (blood pressure should be treated to a target of 140/85 mmHg or lower in non-diabetic persons and 130/80 mmHg or lower in diabetic persons). High risk individuals should monitor their risk profile every 3–6 months.