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    DRAGON Score for Post-TPA Stroke Outcome

    Predicts 3 month outcome in ischemic stroke patients receiving TPA.
    When to Use
    Why Use

    The DRAGON score can help predict 90 day clinical outcomes in patients with ischemic stroke using only data that is available shortly after hospital arrival.

    The DRAGON score was developed to make early predictions about clinical outcomes for ischemic stroke patients using only information that is available shortly after they arrive at the hospital and before tPA is given.

    • Scored on a 0-10 point scale and used to predict clinical outcomes at 90 days (as defined by mRS), lower is better.
    • 96-99% with a DRAGON score of 0 had a good outcome (mRS of 0-2) and none had a miserable outcome (mRS of 5-6).
    • Conversely 97-100% of patients with a DRAGON score of 10 had miserable outcomes (mRS of 5-6).

    Points to keep in mind:

    • The DRAGON score has only been validated in retrospective studies of stroke databases.
    • The authors of the DRAGON score suggest that patients with a miserable predicted outcome should be considered for endovascular therapy or hypothermia, though the benefits of those interventions are unproven and the recommendation is not evidence-based.

    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 DRAGON score, especially at the low and high end of the scale, can help predict which patients are likely to have good clinical outcomes and those who are likely to have miserable clinical outcomes even if given tPA.



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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.
    • Determine the onset of stroke symptoms (or time patient last felt or was observed normal).
    • Obtain a stat head CT to evaluate for hemorrhagic stroke.
    • 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

    • For patients with a DRAGON score that predicts a miserable outcome even if tPA is given, consider the risk/benefit of giving IV thrombolytics.
    • These patients may also be potential candidates for endovascular thrombectomy, though the benefits of this procedure have not yet been demonstrated in the literature.
    • All treatment decisions should be made in consultation with the patient and/or his/her family whenever possible.


    Addition of the selected points; points assigned below:

    Facts & Figures

    Criteria Value
    Dense Cerebral Artery or Early Infarct Signs on Computerized Tomography
    No 0
    One of these +1
    Both +2
    mRS >1, Prestroke
    No 0
    Yes +1
    <65 0
    65-79 +1
    ≥80 +2
    Glucose Level at Baseline
    <8 mmol/L (144 mg/dL) 0
    >8 mmol/L (144 mg/dL) +1
    Onset to Treatment Time
    ≤ 90 minutes 0
    >90 minutes +1
    Baseline NIHSS
    0-4 0
    5-9 +1
    10-15 +2
    >15 3

    Score interpretation:

    DRAGON Score Outcome mRS Score Percentage of Cohort
    0 - 1 Good 0 - 2 96%
    2 Good 0 - 2 88%
    3 Good 0 - 2 78%
    8 - 10 Good 0 - 2 0%
    0 - 1 Miserable 5 - 6 0%
    2 Miserable 5 - 6 2%
    3 Miserable 5 - 6 5%
    8 Miserable 5 - 6 70%
    9 - 10 Miserable 5 - 6 100%

    Evidence Appraisal

    • The DRAGON score was derived by analysing data from 1,319 ischemic stroke patients treated at single center in Finland.
      • The score was then externally validated in this same study by applying it to 330 patients who had been treated at a center in Switzerland.
      • AUC-ROC was 0.84 (0.80-0.87) in the derivation cohort and 0.80 (0.74-0.86) in the validation cohort.
      • Patients with basilar artery occlusions were excluded from this study due to differences in their natural history and treatment protocols.
    • A Spanish study of 297 elderly patients aged 65-80 years (average age = 75), similarly found that the DRAGON score was able to predict good and poor clinical outcomes, with and AUC-ROC of 0.84.
    • A large, multi-center study of 4,519 subjects with ischemic stroke which retrospectively applied the DRAGON score again found that the score performed well.
      • This trial included both anterior and posterior circulation strokes.
      • AUC-ROC was 0.84 (0.82-0.85).
      • No patient with a DRAGON score of 8-10 has a good outcome at 90 days.
    Dr. Daniel Strbian

    About the Creator

    Daniel Strbian, MD, PhD, is a practicing neurologist at the University of Helsinki Central Hospital in Finland. He is an active researcher in the field of ischemic stroke.

    To view Dr. Daniel Strbian's publications, visit PubMed

    Content Contributors
    About the Creator
    Dr. Daniel Strbian
    Content Contributors