HERMES-24 Score Derivation and Validation for Simple and Robust Outcome Prediction After Large Vessel Occlusion...

Area of Science:

• Neurology
• Clinical Decision-Making
• Stroke Medicine

Background:

• Clinicians require simple, predictive prognostic scores for acute ischemic stroke management.
• Developing such a score aids practical decision-making 24 hours post-treatment.

Purpose of the Study:

• To develop and validate a simple prognostic score for 90-day functional outcomes (modified Rankin Scale ≤2).
• The score is intended for patients with anterior circulation acute ischemic stroke, treated with or without endovascular thrombectomy.

Main Methods:

• Utilized the HERMES collaboration dataset (n=1764) with derivation (n=430) and validation (n=441) cohorts.
• Logistic regression identified predictors: National Institutes of Health Stroke Scale score at 24 hours and age.
• Validated the derived HERMES-24 score in control arms and external cohorts (ESCAPE-NA1, INTERRSeCT).

Main Results:

• The HERMES-24 score (age/10 + NIHSS at 24h) demonstrated high predictive accuracy (c-statistic 0.907-0.914) across cohorts.
• The score effectively stratified risk: low probability of good outcome (mRS ≤2) for scores ≥25, high probability for scores <10.
• External validation in ESCAPE-NA1 and INTERRSeCT confirmed predictive performance (c-statistics 0.894 and 0.889).

Conclusions:

• The post-treatment HERMES-24 score is a simple, validated tool for predicting 3-month outcomes in anterior circulation large vessel occlusion stroke.
• It is applicable regardless of treatment (endovascular thrombectomy or not).
• The score facilitates early (day 2) prognostic discussions with families.