Background: As outcomes from allogeneic bone marrow transplantation (BMT) improve, monitoring for longer-term complications becomes increasingly important. Decline in bone health post BMT is well-established, although the pathophysiology may be unique1. Trabecular bone score (TBS) is opportunistically acquired during DXA scans, assesses vertebral micro-architecture and has established utility in fracture risk prediction. As glucocorticoid use in BMT subjects is known to cause vertebral fragility, TBS may be a useful adjunct to triage patients for anti-resorptive treatment.
Aims: To compare the change in bone mineral density (BMD) and TBS in patients pre and post BMT.
Methods: All patients who underwent BMT and had a DXA scan performed between 2019 and 2021 at the Royal Melbourne Hospital, including a pre BMT and post BMT DXA were included. Patient characteristics and DXA values were collected from the electronic medical record and TBS iNsight was used to calculate TBS.
Results: 207 patients were identified, of which 50 had scans pre and post BMT. 35 of these 50 patients (70%) were male and the mean BMI was 27.3 ± 5.29kg/m2. 26 (52%) had related donors, 8 (16%) underwent total body irradiation and 33 (66%) had graft versus host disease. There were statistically significant decreases in T-scores and TBS post BMT (Figure 1), with no significant correlation between relative declines in T-score and TBS (Table 1). Separately evaluating the 82 DXA scans performed post BMT, there was a non-statistically significant increase in FRAX 10-year fracture risk when the calculation was adjusted for TBS (Figure 2).
Conclusions: Bone density and TBS decline significantly post transplantation. TBS provides a distinct, complementary method for assessing fracture risk post BMT and should be considered in this population to triage patients for anti-resorptive therapy.