A low body mass index is correlated with poor survival after allogeneic stem cell transplantation

Background and Objectives. The purpose of this study was to determine whether body mass index (BMI, kg body weight/height (in m(2)) is related to survival in recipients of allogenic stem cell transplantation (ASCT). Design and Methods. Since 1977, 544 adult patients (age ranging from 18 to 64 years) diagnosed with hematologic malignancies, 172 acute myeloid leukemia, 83 acute lymphocytic leukemia, 190 chronic myeloid leukemia and 99 others, underwent myeloablative conditioning and ASCT. Low BMI (<20) was seen in 88 patients, normal BMI (20-25) in 290 and high BMI (>25) in 166 patients. The donors were 348 HLA-identical siblings, 157 matched unrelated donors and 39 HLA major mismatched donors. We assessed BMI as a risk-factor controlling for other risk-factors regarding transplant-related mortality, survival and relapse-free survival using the Cox regression model. Results. Patients with a low BMI more often has ALL, were younger, were more often conditioned with total body irradiation and more often received monotherapy as immunosuppression against graft-versus-host disease. BMI had no effect on engraftment, transfusions and acute or chronic GVHD. Patients with BMI <20 had a higher incidence of alpha-streptococcal septicemia (p=0.005) than did patients with BMI greater than or equal to20, but both groups had a similar incidence of overall bacteremia. Five-year survival was 36% in those with low BMI, 47% in those with normal BMI and 55% in those with high BMI. In multivariate analysis, death was associated with BMI <20 (p=0.023). Other significant factors, adjusted for were: diagnosis of acute lymphoblastic leukemia, donors other than HLA-identical siblings, disease stage beyond fist complete remission or 1(st) chronic phase, transplantation before 1993 and total body irradiation vs. busulfan conditioning. Interpretation and Conclusions. A low BMI (<20) was significantly correlated with an increased transplant-related mortality, a decreased survival and relapse-free survival after ASCT. BMI should be considered when analyzing outcome after ASCT.