9175 Pretransplant Clinical Characteristics Related To Change In Bone Mineral Density In Adults 1 Year After Allogeneic Hematopoietic Stem Cell Transplantation At Bucaramanga, Colombia Reference Center

Abstract Disclosure: G.A. Parra-Serrano: None. C.L. Sossa: None. K.J. Moreno Medina: None. M. Ochoa: None. A. Reyes Gonzalez: None. A. Plata: None. P. Mantilla Mantilla: None. Introduction: Hematopoietic stem cell transplantation (HSCT) , refractory to pharmacological management, increases 10-year survival by 80%, Chronic complications include alterations in bone metabolism, that increase appearance of osteoporosis (13.8 - 17%), non traumatic fractures, and loss of Bone mineral density (BMD) at the hip -4.2%, L1L4 -2% and femoral neck-9%. Methods Calculate Change at (BMD) in adults undergoing allogenic (HSCT) after 1y and determine pretransplant factors related to this change. Composite endpoint osteoporosis/lowbonemass (osteoporosis Tscore<-2.5 and/or low bone mass Zscore-2.0) 1 year after transplant, Adult patients Retrospective cohort study, ethical comittee approval, anonymized database, undergoing allogeneic (HSCT) between 2009 and 2022, (BMD) measured at lumbar spine (L1L4) and femoral neck before and one year after transplant; Also paraclinical variables: TSH, vitaminD, kidney function, glucocorticoid, Graft vs host disease, disease relapse, diabetes. Descriptive analisis performed, simple linear regresion analisis for delta L1L4 and femoral neck BMD before and 1 year after transplant, and multivariate regresion analisis for variables p<0.2 on simple lineal regression analysis . Results 123 patients, (48 included, 73 excluded (22 died, 50 densitometry data not suitable)). BMD change At lumbar spine, -4.7% (NS) , and at femoral neck -9.8% (p<0.05), Simple regression analysis no correlation for preclinical variables at lumbar spine. negative correlation between prednisolone dose at femoral neck BMD (p 0.007, coefficient B -0.0086 [IC95% -0.014, 0.0025]). Mutivariate regression analysis performed for BMD diference at femoral neck, after adjusting for variables p<0.2 on simple regression analysis, model that include (prednisone dose, diabetes and relapse before transplant showed Rsquare 0.19 coefficient 0.0092 p 0.003. For every gram of glucocorticoid (prednisolone) bone loss decrease -0.9% of BMD at femoral neck at 1 year follow up. Proportion of patients with composite osteoporosis/lowbonemass at femoral neck pre-transplant (n2) 4.17%, postransplant (n14) 29.17%. * p 0.0005. no difference observed at lumbar spine. Fracture incidence n2 (4%) at lumbar spine and n1 (2%) at femoral neck. Conclusions At femoral neck, People with HSCT present significant decrease in (BMD) and higuer incidence of Osteoporosis or low bone mass, not observed at lumbar spine, after adjusting for multiple variables. for every 1gr of prednisolone equivalent dose, (BMD) decrease -0.9%, at femoral neck p0.003. The model only explain 19% of change of BMD at femoral neck, that suggest immune response caused by allogenic transplantation might be responsible, in part, of BMD change. Presentation: 6/3/2024