CT biomarkers improve postoperative mortality prediction
Adding automated CT biomarkers to an ICD-based frailty score raised one-year mortality prediction AUROC from 0.75 to 0.79 in 7,638 surgery patients.
Journal of the American College of Surgeons
In a retrospective cohort of 7,672 patients undergoing non-emergent surgery at a tertiary academic center, researchers evaluated whether automated CT imaging biomarkers could improve postoperative mortality predictions. They linked abdominopelvic CT scans obtained within six months prior to surgery with an administrative frailty metric, the ICD-based Risk Analysis Index (RAI-ICD). Using an XGBoost algorithm, the team combined RAI-ICD with automated measurements of muscle, adiposity, bone, and aortic calcification into a Unified Multimodal Model.
Across the cohort, one-year mortality was 12.3%. In 7,638 patients included in primary mortality models, RAI-ICD alone yielded an AUROC of 0.75, outperforming every individual CT biomarker. Integrating all imaging biomarkers with RAI-ICD increased the AUROC to 0.79 (P < 0.001) and improved model calibration, shifting the slope from 0.72 to 1.00. The multimodal model also delivered greater clinical net benefit across robust, frail, and very frail patients.
Why it matters
Objective imaging markers of sarcopenia, bone density, and vascular calcification capture physiological aspects of biological aging that diagnostic codes alone can overlook. Combining these structural phenotypes with clinical frailty assessments could better stratify surgical vulnerability in older adults.
Caveats
The investigation was a retrospective study conducted at a single tertiary academic medical center. The authors emphasize that external validation across other healthcare systems is required before the model can be used clinically.
The paper
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Anoushka Lakshmi, Andrea T. Fisher, Julie T Wu, Ramzi Dudum, Robert Downey Boutin, Akshay Sanjay Chaudhari,Stanford Medicine · VA Palo Alto Health Care System
Journal of the American College of Surgeons · 1 Oct 2026