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Machine learning algorithms for population-specific risk score in coronary artery bypass grafting
Abhyuday Kumara Swamy1, Vivek Rajagopal1, Deepak Krishnan1
1Medha Analytics - Advanced analytics & AI, Narayana Health, Bengaluru, India.
A new risk score (NH Score) developed for Indian patients undergoing coronary artery bypass grafting (CABG) significantly outperforms existing scores like the STS Score and EuroSCORE II. This improved NH Score offers better prediction accuracy for mortality and morbidity in this population.
Area of Science:
- Cardiovascular Surgery
- Medical Informatics
- Health Outcomes Research
Background:
- Existing risk prediction scores for coronary artery bypass grafting (CABG) may not accurately reflect the outcomes in the Indian population.
- Development of a population-specific risk score is crucial for improving surgical decision-making and patient management.
Purpose of the Study:
- To develop and validate a novel risk prediction score (NH Score) tailored for Indian patients undergoing CABG.
- To compare the performance of the NH Score against established scores, namely the Society of Thoracic Surgeon (STS) Score and EuroSCORE II.
Main Methods:
- Utilized baseline data from 6703 adult patients who underwent CABG between 2015 and 2021, splitting it into training (n=5561) and validation (n=1142) sets.
- Employed the CatBoost algorithm for training the NH Score, assessing performance using Precision-Recall Curve, F1 Score, Brier Score, and calibration errors on the validation set.
Main Results:
- The NH Score demonstrated superior performance over both STS Score and EuroSCORE II across all evaluated outcomes, including mortality and morbidity.
- For mortality prediction, the NH Score achieved a significantly higher PR AUC (0.463) compared to STS (0.113) and EuroSCORE II (0.146) (p < 0.0001).
- The NH Score also showed improved prediction accuracy for morbidity and prolonged ventilation compared to the STS Score.
Conclusions:
- The NH Score represents a significant advancement in risk prediction for CABG patients within the Indian population, outperforming current international scores.
- Further validation of the NH Score on larger datasets is recommended to solidify its clinical utility.
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