Comorbidity-age index: a clinical measure of biologic age before allogeneic hematopoietic cell transplantation

J Clin Oncol. 2014 Oct 10;32(29):3249-56. doi: 10.1200/JCO.2013.53.8157. Epub 2014 Aug 25.


Purpose: Age has long been used as a major factor for assessing suitability for allogeneic hematopoietic cell transplantation (HCT). The HCT-comorbidity index (HCT-CI) was developed as a measure of health status to predict mortality risk after HCT. Whether age, comorbidities, or both should guide decision making for HCT is unknown.

Patients and methods: Data from 3,033 consecutive recipients of HLA-matched grafts from five institutions contributed to this analysis. Patients were randomly divided into a training set to develop weights for age intervals and a validation set to assess the performance of prognostic models.

Results: In the training set, patients age 20 to 39 years, 40 to 49 years, 50 to 59 years, and ≥ 60 years had hazard ratios for nonrelapse mortality (NRM) of 1.21 (P = .29), 1.48 (P = .04), 1.75 (P = .004), and 1.84 (P = .005), respectively, compared with those age younger than 20 years. Consequently, age ≥ 40 years was assigned a weight of 1 to be added to the HCT-CI to constitute a composite comorbidity/age index. In the validation set, the composite comorbidity/age score had statistically significantly higher c-statistic estimates for prediction of NRM (0.664 v 0.556; P < .001) and survival (0.682 v 0.560; P < .001) compared with age, respectively. Patients with comorbidity/age scores of 0 to 2 had comparable mortality risks regardless of conditioning regimens. Patients with scores of 3 to 4 and ≥ 5 had statistically significant higher mortality risks after high-dose versus nonmyeloablative regimens.

Conclusion: Age is a poor prognostic factor. The proposed composite measure allows integration of both comorbidities and age into clinical decision making and comparative-effectiveness research of HCT.

Publication types

  • Multicenter Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Factors
  • Aged
  • Comorbidity
  • Decision Making*
  • Female
  • Health Status Indicators*
  • Hematologic Neoplasms / therapy*
  • Hematopoietic Stem Cell Transplantation*
  • Humans
  • Male
  • Middle Aged
  • Prognosis
  • Retrospective Studies
  • Transplantation, Homologous
  • Treatment Outcome