Distribution and Impact of Comorbidities on Survival and Leukemic Transformation in Myeloproliferative Neoplasm-Associated Myelofibrosis: A Retrospective Cohort Study

Abstract Background We sought to describe the distribution and impact of comorbidities on outcomes in patients with myelofibrosis, a disease characterized by aberrant bone marrow function with eventual fibrosis. Comorbidities were scored using the Adult Comorbidity Evaluation-27 (ACE-27) and the Hematopoietic Cell Transplant Comorbidity Index (HCT-CI), in which a score ≥ 3 indicates severe comorbidities. Patients and Methods We conducted a retrospective study of 306 patients with a confirmed diagnosis of myelofibrosis. Patients were seen from 1999 to 2014 with a median follow-up of 2 years. Multivariable Cox proportional hazards models were constructed to assess the impact of comorbidities on overall survival and leukemic transformation from the date of presentation to our center. A series of descriptive analyses were performed examining the distribution of comorbidities captured by the scales. Results On multivariable survival analysis, an ACE-27 score of 3 was associated with an almost twofold increase in the risk of all-cause death (hazard ratio [HR] 1.95; 95% confidence interval [CI], 1.06-3.58; P  = .03) compared with a lower score of 0 to 1. An HCT-CI score ≥ 3 was marginally significantly associated with an increased risk of all-cause death (HR 1.60; 95% CI 0.96-2.68; P  = .07). ACE-27 captured a greater spectrum of cardiovascular and venous thrombotic disease. No impact of comorbidities on leukemic transformation was observed. Conclusions Although the presence of severe comorbidities was lower when assessed by ACE-27 (13%) compared with HCT-CI (23%), and the spectrums of comorbidities captured were different, the overall impact of severe comorbidities as assessed by both scales appears to be similar and associated with a survival disadvantage.