Objective: To investigate the impact of body mass index (BMI) before transplantation on clinical outcomes of haploidentical allogeneic stem cell transplantation (allo-HSCT).
Methods: We performed a retrospective cohort study of 253 adult patients with acute or chronic leukemia who received haploidentical allo-HSCT from August 2008 to September 2011. All conditioning regimens were myeloablative and bulsufan based. Patients were stratified according to BMI values (low BMI group: <18 kg/m(2); normal BMI group: ≥ 18 and < 25 kg/m(2); overweight BMI group: ≥ 25 kg/m(2)). Other possible risk factors correlated with GVHD, relapse, transplant related mortality (TRM) and overall survival (OS) included age and gender of donor and recipient, HLA disparity, relationship between donor and recipient, diagnosis, status of disease, ATG dose in conditioning regime(10 mg/kg , 6 mg/kg), mononuclear cells (MNC), CD(+)34 and CD(+)3 cell amount from granulocyte colony-stimulating factor (G-CSF) primed bone marrow grafts (G-BM) and G-CSF mobilized peripheral blood grafts(G-PB). Cox regression analysis was used to determine the related risk factors.
Results: The median age of all 253 patients was 31 (18-56) years, including 128 cases with acute myeloid leukemia (AML), 95 cases with acute lymphocytic leukemia (ALL), and 30 cases with chronic myeloid leukemia (CML). According to primary diseases, 185 patients were classified in the standard -risk group and 68 cases in the high-risk group. Median follow-up time was 929 days (range: 48-1762 days) post-transplantation. Engraftment has been attained 252 (99.6%) recipients with the median time of granulocyte and platelet recovery 12 days (ranging from 9 to 45 days) and 16 days (ranging from 7 to 180 days), respectively. Cumulative incidences of acute GVHD was 33.2% with median time of 25 days (range: 13-88 days) after transplant. Multivariate analysis identified that low BMI was associated with an increased risk of grade III-IV acute GVHD (HR = 5.736, 95%CI 1.779-18.491, P = 0.003). There was no significant impact of BMI to other manifestations of GVHD, TRM, relapse or OS in different groups.
Conclusions: Our findings demonstrate a correlation between pre transplant BMI and clinical outcome post-transplant. Low BMI was associated with increased risk of severe acute GVHD in leukemia patients receiving haploidentical allo-HSCT. Meticulous supportive care pre-transplantation is required for low BMI patients.