Objective:
Pretransplant CT body composition measures can provide prognostic value in deceased-donor liver transplant outcomes. Previous research has shown conflicting results for sarcopenia and myosteatosis as relevant pretransplant risk factors. Our purpose was to quantify the potential of fully automated CT-based body composition metrics in predicting liver transplant recipient postoperative outcomes.
Materials and Methods:
Fully automated artificial intelligence-based body composition tools were applied to pretransplant abdominal CT scans in a retrospective cohort of deceased-donor liver transplant recipients. Outputs for body composition included measurements for liver (volume and attenuation), spleen (volume and attenuation), L3-level skeletal muscle (area and attenuation), L1-level trabecular bone mineral density (BMD), abdominal aortic calcium (Agatston score), and L3-level areas and attenuation for visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT). Age- and sex-corrected hazard ratios (HRs) were analyzed according to highest-risk quartiles compared with the other quartiles combined. Area under the receiver operating characteristic curve (ROC AUC) analysis in univariate and multivariate scenarios were also performed.
Results:
There were 598 first-time recipients (median age, 56 years [IQR, 49 - 61]; 383 men, 215 women) were included in this study with transplant dates from 2005 - 2021. Mean clinical follow-up interval after transplant was 8.6 ± 4.47 years with 224 deaths (mean interval, 5.3 ± 3.9 years posttransplant), and 246 graft failures (mean interval, 4.7 ± 4.0 years posttransplant) observed. HRs included 1.53 (95% CI, 1.14 - 2.06) for L3-level muscle attenuation (<em>p</em> < .01), 1.66 (95% Cl, 1.24 - 2.22) for aortic Agatston score (<em>p</em> < .001), 1.35 (1.02 - 1.80) for L3 SAT area (<em>p</em> < .05), and 1.82 (1.35 - 2.46) for liver volume (<em>p</em> < 0.001). Multivariate 10-year AUC for predicting mortality was 0.675 using liver volume, aortic Agatston score, and muscle attenuation.
Conclusion:
Automated CT measurements of muscle density, abdominal aortic calcification, abdominal fat, and liver volume are predictive of mortality in first-time liver transplant recipients.