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    Patent Pending

    THRIVE Score for Stroke Outcome

    Estimates prognosis after an acute ischemic stroke.
    When to Use
    Why Use

    The THRIVE score can help physicians predict several key outcomes in patients suffering an ischemic stroke.

    The Total Health Risk In Vascular Events (THRIVE) score uses NIHSS score, age, and chronic disease to predict long-term neurologic outcomes in stroke patients.

    • Scored on a 0-9 point scale, lower is better.
      • A score of 0 predicts a 79-88% chance of a good neurological outcome and 0-2% predicted mortality at 90 days.
      • A score of 9 predicts a 7-16% chance of a good neurological outcome and 38-58% mortality at 90 days.
      • Note: A newer outcome measure is now performed using the THRIVE-c calculation, which uses continuous age and NIHSS to more accurately determine outcome probability.
    • Risk of hemorrhagic conversion increases proportionally for each additional point in the THRIVE score.
    • The THRIVE score performs well when applied to stroke patients who received IV tPA as well as patients who did not receive thrombolysis or endovascular intervention.

    Points to keep in mind:

    • The THRIVE score has been validated only retrospectively in various stroke databases and has not been applied prospectively.

    There are nearly 800,000 cases of acute stroke in the United States every year, with 130,000 associated deaths (4th leading cause of death in Americans).

    The THRIVE score can help physicians predict functional outcome, death after stroke, and the risk of brain hemorrhage after IV tPA administration in patients who suffer an ischemic stroke.



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    Next Steps
    Creator Insights


    • Consult Neurology immediately (if available) for all patients presenting with ischemic stroke.
    • Evaluate whether the patient is a potential candidate to receive intravenous thrombolysis (tPA).
    • Consider further imaging including CT, CT angiography and MRI/MRA.


    In patients who present with symptoms concerning for ischemic stroke:

    • Consult Neurology immediately (if available) for all patients presenting with ischemic stroke.
    • Determine the onset of stroke symptoms (or time patient last felt or was observed normal).
    • Consider further imaging including CT, CT angiography and MRI/MRA.
    • In appropriate circumstances and in consultation with both neurology and the patient, consider IV thrombolysis for ischemic strokes in patients with no contraindications.
    • Always consider stroke mimics in the differential diagnosis, especially in cases with atypical features (age, risk factors, history, physical exam), including:
      • Recrudescence of old stroke from metabolic or infectious stress;
      • Todd’s paralysis after seizure;
      • Complex migraine;
      • Pseudoseizure, conversion disorder.

    Critical Actions

    • The THRIVE score provides reliable early information about the baseline odds of recovery and prognosis in an acute ischemic stroke patient.
    • This information may help guide physicians as well as inform discussions with patients and their families when weighing the risks and benefits of various treatment options.


    Addition of the selected points.

    Facts & Figures

    See formula table, below:

    Criteria Value
    NIH Stroke Scale
    ≤ 10 0
    11-20 +2
    ≥ 21 +4
    ≤ 59 0
    60-79 +1
    ≥ 80 +2
    Hypertension +1
    Diabetes mellitus +1
    Atrial fibrillation +1

    Evidence Appraisal

    • The THRIVE score was derived after analysing data from two single-arm trials of subjects with ischemic stroke who were treated with a thrombectomy device.
    • The THRIVE score was subsequently validated after being applied a prospectively collected database registry of 1000 patients who underwent endovascular thrombectomy for acute ischemic stroke. (Flint AC 2012)
    • The THRIVE score was then applied to data from the NINDS trials and was found to be a better predictor of outcomes than NIHSS and age alone. (Kamel H 2012)
    • When applied to the the data for the 6483 subjects in the Safe Implementation of Thrombolysis in Stroke - Monitoring Study (SITS-MOST), the THRIVE score was found to predict the risk of symptomatic intracranial hemorrhage after intravenous tPA administration. (Flint AC 2014)


    Dr. Alexander Flint

    From the Creator

    We built the THRIVE score to put real data behind the notion that chronic medical comorbidities can significantly influence ischemic stroke outcomes. It was known that NIHSS and age were major predictors of stroke outcome, so we combined these elements with comorbidities in the score-building data set (the MERCI and Multi-MERCI trials). Three comorbidities were independent predictors in the models : hypertension, diabetes, and atrial fibrillation. Each comorbidity accounted for approximately the same risk of worsened outcome. We went on to validate the THRIVE score in the Merci Registry, the NINDS IV tPA trial, VISTA, the TREVO-2 trial, the SWIFT and STAR trials, and the SITS-MOST study. We found that the THRIVE score works well across the three major acute treatment contexts (IV tPA, endovascular stroke treatment, and no acute treatment) and that THRIVE predicts functional outcome, death after stroke, and the risk of brain hemorrhage after IV tPA administration.

    About the Creator

    Alexander Flint, MD, PhD, is a neurointensivist and stroke specialist at Kaiser Permanente in Redwood City, California. He is also co-founder and CMO of image32, a disruptive cloud-based startup that allows doctors and patients to share medical imaging studies and get second opinions. Dr. Flint's research focuses on the care of patients with stroke and neurological critical illness such as the benefits of statin use early in stroke and on the THRIVE score.

    To view Dr. Alexander Flint's publications, visit PubMed

    Content Contributors
    About the Creator
    Dr. Alexander Flint
    Content Contributors