Recalibrating the Child-Turcotte-Pugh Score to Improve Prediction of Transplant-Free Survival in Patients with Cirrhosis

Dig Dis Sci. 2016 Nov;61(11):3309-3320. doi: 10.1007/s10620-016-4239-6. Epub 2016 Jul 12.

Abstract

Background: The Child-Turcotte-Pugh (CTP) score is a widely used and validated predictor of long-term survival in cirrhosis. However, the cutpoints for stratifying laboratory variables in CTP have never been validated.

Objective: The objective of this study was to identify evidence-based cutpoints for the CTP laboratory subscores to improve its predictive capacity for transplant-free survival.

Design: Retrospective observational study.

Data source: Using a cohort of 30,897 cirrhotic US Veteran patients with at least 5 years of follow-up, we performed Cox proportional hazard survival model iterations varying the upper and lower cutpoints for INR, total bilirubin and albumin CTP subscores. Cutpoints yielding the highest Harrell's C-statistics for concordance with transplant-free survival were incorporated into a modified CTP (mCTP) score. Validation of the mCTP was performed at multiple time frames within the follow-up period of the cohort and within subsets defined by disease etiology.

Results: Modification of CTP cutpoints increased the Harrell's C-statistic for age- and gender-adjusted Cox proportional hazard models from 0.701 ± 0.002 to 0.709 ± 0.002 and the risk ratio per unit change from 1.49 (1.48-1.50) to 1.53 (1.52-1.54). The modified cutpoints showed superiority in predicting 5-year transplant-free survival in various disease etiology subgroups. A mCTP substituting serum creatinine for INR performed superiorly for predicting 5-year transplant-free survival.

Conclusion: We propose an evidence-based recalibration of CTP score cutpoints that optimizes this model's capacity to predict transplant-free survival in patients with cirrhosis. The CTP score remains the best predictor of 5-year overall and transplant-free survival in patients with cirrhosis.

Keywords: Cirrhosis; Creatinine; Human; MELD; Natural history; Predictive models; Survival.

Publication types

  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Bilirubin / blood*
  • Creatinine / blood*
  • Disease Progression
  • End Stage Liver Disease
  • Evidence-Based Medicine
  • Female
  • Humans
  • International Normalized Ratio*
  • Liver Cirrhosis / blood*
  • Liver Cirrhosis / mortality
  • Liver Cirrhosis / surgery
  • Liver Transplantation
  • Male
  • Middle Aged
  • Odds Ratio
  • Prognosis
  • Proportional Hazards Models
  • Retrospective Studies
  • Serum Albumin / metabolism*
  • Severity of Illness Index
  • United States
  • Veterans

Substances

  • Serum Albumin
  • Creatinine
  • Bilirubin