Stroke Risk Calculator

Assess your 10-year stroke risk using validated clinical models. Essential tool for stroke prevention and cardiovascular health.

Framingham Stroke Risk
CHADS₂ Score
CHA₂DS₂-VASc Score
QStroke Algorithm

Framingham Stroke Risk Profile: Estimates 10-year probability of stroke based on age, sex, blood pressure, diabetes, smoking, cardiovascular disease, atrial fibrillation, and left ventricular hypertrophy.

Validated in multiple population studies with good predictive accuracy (C-statistic 0.74-0.79).

Demographics

Enter age between 20 and 100 years

Blood Pressure

Average of at least 2 measurements on separate occasions

Medical History

Lifestyle & Laboratory Factors

Clinical Validation Note: This calculator uses validated algorithms from the Framingham Heart Study and other large cohort studies. Results should be interpreted by healthcare professionals in the context of individual patient factors.

Calculating stroke risk...

Understanding Stroke Risk

Stroke is a medical emergency that occurs when blood flow to the brain is interrupted or reduced, depriving brain tissue of oxygen and nutrients. Stroke risk assessment helps identify individuals at higher risk so preventive measures can be implemented.

Key Clinical Insight: Each 20 mmHg increase in systolic blood pressure above 115 mmHg doubles the risk of stroke. Conversely, each 10 mmHg reduction in systolic BP decreases stroke risk by approximately 30%.

Stroke Types:

Ischemic Stroke

Caused by a blockage in an artery supplying blood to the brain (87% of strokes). Treatment: Thrombolytics within 4.5 hours, thrombectomy within 24 hours.

Hemorrhagic Stroke

Caused by bleeding into or around the brain (13% of strokes). Treatment: Blood pressure control, surgical intervention if indicated.

Transient Ischemic Attack (TIA)

"Mini-stroke" with temporary symptoms; warning sign of future stroke. 10-15% risk of stroke within 90 days, highest in first 48 hours.

Stroke Risk Assessment Models - Clinical Validation

Model Purpose Validation (C-statistic) Clinical Application
Framingham Stroke Risk General stroke risk in healthy individuals 0.74-0.79 Primary prevention, risk stratification
CHADS₂ Stroke risk in atrial fibrillation patients 0.68-0.72 Anticoagulation decision in AF
CHA₂DS₂-VASc Refined stroke risk in atrial fibrillation 0.71-0.75 Better identification of low-risk AF patients
QStroke UK primary care stroke risk 0.77-0.82 UK NICE guidelines, includes ethnicity

Modifiable vs. Non-Modifiable Risk Factors

Non-Modifiable Risk Factors
  • Age: Risk doubles each decade after age 55. 75% of strokes occur in people >65 years.
  • Sex: Men have 1.25x higher incidence, but women have worse outcomes and higher lifetime risk.
  • Race/Ethnicity: African Americans have 2x higher risk than Caucasians.
  • Genetics: Family history increases risk 2-3x. Specific genes identified (NOTCH3, COL4A1).
  • Prior Stroke/TIA: 15-40% risk of recurrent stroke within 5 years.
Modifiable Risk Factors
  • Hypertension: Most important controllable factor. RR 3.0 for stroke.
  • Atrial Fibrillation: Increases risk 5-fold. Anticoagulation reduces risk by 64%.
  • Diabetes: Increases risk 2-4 times. HbA1c >7% significantly increases risk.
  • Dyslipidemia: LDL reduction of 39 mg/dL reduces stroke risk by 21%.
  • Smoking: Current smokers have 2x risk. Risk normalizes 2-5 years after quitting.

Medical Management Based on Risk Level

Clinical Decision Support

1

Low Risk (<5%): Reassess every 2-5 years. Focus on lifestyle maintenance and periodic BP monitoring.

2

Moderate Risk (5-10%): Annual reassessment. Consider aspirin 81mg/day if benefit outweighs bleeding risk.

3

High Risk (10-20%): 6-month follow-up. Consider statin therapy if LDL >100 mg/dL. Tight BP control (<130/80).

4

Very High Risk (>20%): 3-month follow-up. Strongly consider antithrombotic therapy. Refer to cardiology/neurology.

Pharmacological Prevention Guidelines
  • Antihypertensives: ACE inhibitors/ARBs preferred. Goal BP <130/80 for high-risk patients.
  • Statins: High-intensity statins (atorvastatin 40-80mg, rosuvastatin 20-40mg) for secondary prevention.
  • Antiplatelets: Aspirin 81mg or clopidogrel 75mg for non-cardioembolic stroke prevention.
  • Anticoagulants: DOACs preferred over warfarin for AF (apixaban, rivaroxaban, dabigatran).
  • Diabetes Management: Consider SGLT2 inhibitors or GLP-1 agonists with cardiovascular benefit.

Evidence-Based Prevention Strategies

Blood Pressure Control

Goal: <130/80 mmHg for high-risk individuals. Evidence: SPRINT trial showed 30% reduction in cardiovascular events with intensive BP control.

Dietary Modification

DASH Diet: 8-14% reduction in stroke risk. Mediterranean Diet: 30% reduction. Focus on fruits, vegetables, whole grains, fish, and olive oil.

Physical Activity

Recommendation: 150 min/week moderate or 75 min/week vigorous activity. Benefit: 25-30% risk reduction compared to sedentary lifestyle.

Smoking Cessation

Benefit Timeline: Risk drops by 50% at 1 year, equals never-smokers at 5 years. Resources: Nicotine replacement, varenicline, bupropion.

Alcohol Moderation

J-curve Relationship: 1-2 drinks/day may be protective, >2 drinks/day increases risk. Heavy drinking: >4 drinks/day increases risk 5-fold.

Stroke Emergency Response Plan

Time is Brain: 1.9 million neurons die every minute during stroke.

F

FACE: Ask the person to smile. Does one side of the face droop?

A

ARMS: Ask the person to raise both arms. Does one arm drift downward?

S

SPEECH: Ask the person to repeat a simple phrase. Is speech slurred or strange?

T

TIME: If you observe any of these signs, call emergency services IMMEDIATELY. Note time of symptom onset.

Critical Time Windows:

  • tPA (Alteplase): Within 4.5 hours of symptom onset
  • Thrombectomy: Within 24 hours for selected patients
  • Door-to-Needle: Goal <60 minutes
  • Door-to-Puncture: Goal <90 minutes

Monitoring and Follow-up Recommendations

For Healthcare Providers:

  • Annual Assessment: Recalculate stroke risk annually for patients >40 years
  • BP Monitoring: Home BP monitoring recommended for hypertension management
  • Laboratory Tests: Annual lipid profile, HbA1c if diabetic, renal function
  • ECG Screening: Consider annual ECG for patients >65 years to detect AF
  • Carotid Imaging: Consider for patients with bruits or TIA symptoms

Frequently Asked Questions

This calculator uses validated algorithms from the Framingham Heart Study with discrimination (C-statistic) of 0.74-0.79, meaning it correctly ranks risk for approximately 75% of individuals. However, clinical assessment by a healthcare provider includes additional factors not captured here:

  • Physical examination findings
  • Detailed family history
  • Medication adherence
  • Social determinants of health
  • Imaging results (carotid ultrasound, echocardiogram)

Clinical Correlation: This tool is best used as a screening aid and should be followed by comprehensive clinical evaluation.

Primary Prevention (no prior stroke):

  • Not Recommended: For low-risk individuals due to bleeding risk outweighing benefit
  • Consider: For moderate-risk (5-10%) individuals aged 40-70 years
  • Not Recommended: For adults >70 years due to increased bleeding risk

Secondary Prevention (prior stroke/TIA):

  • Recommended: Aspirin 81mg daily or clopidogrel 75mg daily
  • Dual Antiplatelet: Consider aspirin + clopidogrel for 21-90 days after minor stroke/TIA

Important: Always consult with a healthcare provider before starting aspirin therapy.

Based on the INTERSTROKE study, modifying 10 risk factors could prevent 90% of strokes:

  1. Hypertension Control: Most important (48% population attributable risk)
  2. Physical Activity: 150 min/week moderate activity (36% risk reduction)
  3. Healthy Diet: DASH or Mediterranean diet (19% reduction)
  4. Smoking Cessation: 12% population attributable risk
  5. Weight Management: BMI <25 kg/m² (19% reduction)
  6. Diabetes Control: HbA1c <7% (4% population attributable risk)
  7. Alcohol Moderation: ≤2 drinks/day for men, ≤1 for women
  8. Stress Management: Meditation, yoga, counseling
  9. Lipid Management: LDL <100 mg/dL (high risk), <70 mg/dL (very high risk)
  10. Atrial Fibrillation Management: Anticoagulation when indicated

Reassessment Frequency Based on Risk Category:

  • Low Risk (<5%): Every 3-5 years or with significant life/health changes
  • Moderate Risk (5-10%): Annually
  • High Risk (10-20%): Every 6 months
  • Very High Risk (>20%): Every 3-6 months

Triggers for Immediate Reassessment:

  • New diagnosis of hypertension, diabetes, or atrial fibrillation
  • Hospitalization for cardiovascular event
  • Significant weight change (>5% body weight)
  • Change in smoking status
  • New symptoms (palpitations, dizziness, transient weakness)

Yes, women have unique risk factors and considerations:

Women-Specific Risk Factors:

  • Pregnancy-related: Preeclampsia (doubles stroke risk), gestational diabetes
  • Hormonal: Oral contraceptives (especially with smoking or migraine with aura)
  • Menopausal: Hormone replacement therapy (increases risk if started >10 years after menopause)
  • Autoimmune: Higher prevalence of lupus, antiphospholipid syndrome
  • Atrial Fibrillation: Higher prevalence after age 75, more often asymptomatic

Women-Specific Prevention Strategies:

  • Blood Pressure: More aggressive control in pregnancy and postpartum
  • Migraine with Aura: Avoid smoking and estrogen-containing contraceptives
  • Preeclampsia History: Annual cardiovascular risk assessment
  • Screening: Earlier AF screening (consider at age 65 vs 75 for men)
  • Depression: Treat depression as it's more prevalent and increases stroke risk in women