Loss of bone mass and vitamin D deficiency after hematopoietic stem cell transplantation: standard prophylactic measures fail to prevent osteoporosis.

Bone mineral density (BMD) and biochemical markers of bone metabolism were analyzed in 67 adults with ALL (n = 27), AML (n = 14), MDS (n = 6) and CML (n = 20) before and after allogeneic stem cell transplantation (SCT). Median age was 36 years (17-56). Twenty-six out of 53 patients (49%) had osteopenia and osteoporosis before SCT, 21/26 had acute leukemias and 5/26 had chronic myeloid leukemia (CML). T-score before SCTwas -1.23 in patients with acute leukemias and 0.62 in CML patients (P = 0.001). After SCT, a significant loss of BMD was observed in all patients. After 6 months, 24 of 36 evaluable patients (67%) had pathologic BMD, 11 of them (30%) had developed osteoporosis. After 12 months, 20 of 32 evaluable patients (62%) had BMD values below normal and nine of them (28%) had osteoporosis. Increased pyridinium excretion was observed in 12/20 patients (60%) with acute leukemias, but only in 3/13 (23%) with CML (P = 0.014). A prolonged vitamin D deficiency for more than 6 months developed early after SCT in all patients. Patients with acute leukemias frequently have osteopenia and osteoporosis before SCT. After SCT, a further loss of BMD occurs independent from the underlying disease. Standard prophylactic measures are not sufficient to prevent loss of bone mass. Studies on prophylactic interventions are needed to prevent severe osteoporosis in long-term survivors of SCT.