Abstract 67: RNA Expression Differentiates Large Artery And Cardioembolic Stroke: A Pilot Analysis From The BASE Trial
Bibliographic record
Abstract
Background: An accurate test to differentiate large artery stroke patients from those with cardioembolic stroke would be of significant utility. Using the Biomarkers of Acute Stroke Etiology (BASE) trial (NCT02014896) dataset, our purpose was to determine if blood gene expression signatures accurately differentiate large artery stroke patients from those with cardioembolic stroke. Methods: The BASE trial enrolled suspected stroke patients presenting to 10 hospitals within 8 hours of symptom onset. Gold standard diagnosis was per local neurologist adjudication blinded to RNA testing. The final gold standard diagnosis was determined by an adjudication committee blinded to RNA test results. Whole blood, obtained in PAX tubes, was frozen at -20C within 72 hours and analyzed at a core lab (Ischemia Care, LLC, Blue Ash, OH) using Affymetrix HTA micro arrays. Significantly differentially expressed genes (p<0.005) were identified by calculating an empirical Bayes moderated t-statistic contrasting expression in large artery and cardioembolic stroke patients. Differentially expressed genes were used as input to a multi-layer perceptron neural network to derive a 66-gene diagnostic signature. Results: Overall, 32 patients were enrolled, 8 (25%) with large artery stroke and 24 (75%) with cardioembolic stroke; 50% were male, and median (IQR) age was 68.6 (47,88). Median (IQR) time from symptoms to presentation was 102.5 (14, 450) minutes. Coexistent pathology at presentation was atrial fibrillation in 13 (41%), heart failure 7 (22%), prior stroke 7 (22%), and coronary artery disease 8 (25%). The resulting gene signature distinguished large artery stroke from cardioembolic stroke; C-statistic 0.99 (0.94-1.0, 95% CI), sensitivity 0.91 (0.56-1.0, 95% CI), at a fixed specificity of 0.95, as observed in 5-fold cross validation of the training data. Conclusion: RNA expression differentiates large artery stroke patients from those with cardioembolic stroke, and may have therapeutic and outcome implications.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.006 | 0.007 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.002 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".