Impact of comorbidity indexes on non-relapse mortality.

Comorbidity indexes (CI) have been reported to predict non-relapse mortality (NRM) and overall survival after allogeneic hematopoietic stem cell transplantation (HSCT) (Charlson's comorbidity index (CCI), hematopoietic cell transplantation CI (HCT-CI) and the pre-transplantation assessment of mortality (PAM) score). Which of these indexes best predict survival is unknown yet. We retrospectively studied 286 patients who underwent allogeneic HSCT. HCT-CI and PAM scores required grading according to pre-transplant pulmonary function tests (PFTs), which were lacking for some patients. We thus designed a reduced HCT-CI and an adjusted PAM, without results of PFTs. Using CCI, 25% of patients had indexes of 1 or more; median reduced HCT-CI score was 1; median adjusted PAM score was 24. The discriminative properties of the three CIs were rather low in our population. Comparison of patients and transplant characteristics between our and Seattle group's cohorts, however, revealed significant differences in more children, in more cord blood HSCT and in HSCT for Fanconi anemia in St Louis. Finally, multivariate analysis of scoring items revealed that age, matched unrelated or mismatched donor and hepatic disease were associated with NRM in our cohort. Translating use for patient's counseling or decision to proceed to transplant of these CIs will need prospective studies in a large independent cohort.