Increased risk of hip and major osteoporotic fractures in 8463 patients who have undergone stem cell transplantation, a Swedish population-based study.

Abstract

To explore the risk for osteoporotic fracture in patients who have undergone hematopoietic stem cell transplantation (HSCT) compared with the Swedish population. The risk of osteoporotic fractures was determined in a retrospective population cohort study of adult (≥ 18years) Swedish patients (n = 8463), who were transplanted with HSCT 1997-2016 and compared with all adults living in Sweden during the same period. In the total study group (n = 8463), 90 hip fractures (1.1% both in males and females) and 361 major osteoporotic fractures (MOF) (3.2% in men and 6.0% in women) were identified. In the total study population, the ratio of observed and expected number of hip fracture for women was 1.99 (95% CI 1.39-2.75) and for men 2.54 (95% CI 1.91-3.31). The corresponding ratio for MOF in women was 1.36 (CI 1.18-1.56) and for men 1.61 (CI 1.37-1.88). From 2005 onwards, when differentiation in the registry between allo- and auto-HSCT was possible, the observed number of hip fracture and MOF in allo-HSCT (n = 1865) were significantly increased (observed/expected hip fracture 5.24 (95% CI 3.28-7.93) and observed/expected MOF 2.08 (95% CI 1.63-2.62)). Fractures occurred in mean 2.7 (hip) and 2.5 (MOF) years after allo-HSCT. Graft-versus-host disease (GVHD) was not associated with an increased risk of fracture. Patients who underwent HSCT had an increased risk of both hip and major osteoporotic fracture compared with the Swedish population and occurred in 4.3% of patients. GVHD was not statistically significantly associated with fracture risk.