What does this tool measure?
This interactive tool measures the
chance of having a
stroke in the next 5 years, for people who are age 55
or older and have
atrial fibrillation. To calculate your score, the tool
uses the information you enter.
This tool is based on information
from the Framingham Heart Study. Since 1948 the Framingham Heart Study has
studied the progression of heart disease and its risk factors. The data from
this study has been used to make a risk assessment.
You should be
aware, though, that the tool cannot be applied to everyone. This tool does not
work for people who:
- Have
mitral valve stenosis or significant left ventricular
dysfunction, which interferes with the heart's ability to pump well.
- Are already taking an anticoagulant such as warfarin (Coumadin).
Anticoagulants, also called blood thinners, prevent clots from forming and greatly lower the risk of
stroke.
- Have had a stroke or transient ischemic attack within 30
days of developing atrial fibrillation. If so, you are already at high risk,
and this tool will not work for you.
The values you enter include the most important risk
factors for stroke. They are:
- Age and gender. The risk
of stroke increases with age. The risk doubles every decade after age 55. Also,
among those with atrial fibrillation, women have a higher risk of stroke than
men.
- Systolic blood pressure. Systolic blood
pressure is the first number of your blood pressure reading. For example, if
your reading is 120/80 (120 over 80), your systolic blood pressure is 120
millimeters of mercury (mm Hg).
- Diabetes.
Having diabetes increases your risk of stroke. You can help lower this risk by
working with your doctor to keep your blood sugar levels in a target range.
- Prior stroke or transient ischemic attack (TIA). If you have had a stroke or a transient ischemic
attack (TIA) within 30 days of developing atrial fibrillation, you are already
at high risk, and this tool will not work for you. But if you had a prior
stroke or TIA before you developed atrial fibrillation, this tool will work for
you.
What does your score mean?
Your score will appear
in as a value from 1% to 99%. If your score is 5%, it means that 5 out of 100
people with this level of risk will have a stroke in the next 5 years. If your
score is 10%, it means that 10 out of 100 people with this level of risk will
have a stroke in the next 5 years.
These percentages are one way
your doctor can decide if an anticoagulant (blood thinner), such as warfarin, is the right medicine to help lower your risk of stroke. Talk with your doctor about the best
way to lower your risk of stroke.
If you are above a 10%
risk, talk to your doctor about taking an anticoagulant. You will want to weigh the benefits of reducing your risk of stroke against the risks of taking an anticoagulant. These medicines work well to prevent stroke. But they also increase the risk of bleeding.
If you are at a 10% risk or
lower, you may get enough protection from stroke by taking aspirin. Aspirin may be a good choice if you are young and have no other heart or health problems or if you can't take an anticoagulant safely. Aspirin doesn't work as well as an anticoagulant to reduce your stroke risk. But aspirin is less likely to cause bleeding problems.
Other antiplatelet medicines, such as clopidogrel (Plavix), may be used. Your doctor may have you take them with aspirin or instead of aspirin. When aspirin and clopidogrel are used together, they may reduce the risk for stroke more than aspirin alone. But this combination is also more likely to cause bleeding than aspirin alone.
What's next?
Talk to your doctor about how to lower
your risk of stroke if you have atrial fibrillation. Medicine and lifestyle changes, such as quitting smoking or eating a heart-healthy diet, can help lower your risk of stroke.
For help deciding if taking an anticoagulant is right for you, see:
Atrial Fibrillation: Should I Take an Anticoagulant to Prevent Stroke?
For help deciding which anticoagulant to take, see:
- Atrial Fibrillation: Which Anticoagulant Should I Take to Prevent Stroke?
For more information, see the topic
Atrial Fibrillation.
This tool
was derived from Wang TJ, et al. (2003). A risk score for predicting stroke or
death in individuals with new-onset atrial fibrillation in the community: The
Framingham heart study. JAMA, 290(8): 1049–1056. The
Framingham Heart Study is a project of the National Heart, Lung, and Blood
Institute, a part of the National Institutes of Health and the U.S. Department
of Health and Human Services, and Boston University. More information is
available online at www.framinghamheartstudy.org.
References
Other Works Consulted
- Fuster V, et al. (2006). ACC/AHA/ESC 2006 guidelines
for the management of patients with atrial fibrillation—Executive summary. A
report of the American College of Cardiology/American Heart Association Task
Force on Practice Guidelines and the European Society of Cardiology Committee
for Practice Guidelines (Writing committee to revise the 2001 guidelines for
the management of patients with atrial fibrillation). Circulation, 114(7): 700–752. [Erratum in Circulation, 116(6): e137.]
- Wang TJ, et al. (2003). A risk score for predicting
stroke or death in individuals with new-onset atrial fibrillation in the
community: The Framingham heart study. JAMA, 290(8):
1049–1056.
- Wann LS, et al. (2011). 2011 ACCF/AHA/HRS Focused update on the management of patients with atrial fibrillation (updating the 2006 guideline): A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation, 123(1): 104–123.
- Wann LS, et al. (2011). 2011 ACCF/AHA/HRS focused updated on the management of patients with atrial fibrillation (update on dabigatran): A report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation, 123(10): 1144–1150.
Credits
| By | Healthwise Staff |
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| Primary Medical Reviewer | E. Gregory Thompson, MD - Internal Medicine |
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| Specialist Medical Reviewer | John M. Miller, MD, FACC - Cardiology, Electrophysiology |
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| Last Revised | November 30, 2010 |
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