Associations of serum sclerostin with bone mineral density, markers of bone metabolism and thalassaemia characteristics in adult patients with transfusion-dependent beta-thalassaemia

Aim of the study: To assess serum sclerostin in transfusion-dependent beta-thalassaemia patients versus healthy controls and to examine its associations with bone mineral density, bone metabolism markers and beta thalassaemia alterations. Material and methods: Sixty-two transfusion-dependent beta-thalassaemia (TDssT) patients and 30 healthy controls were evaluated for serum sclerostin, osteocalcin, beta-cross laps, osteoprotegerin and serum level of receptor activator of nuclear factor kappa-Beta ligand (sRANKL). Bone mineral density was measured at the lumbar spine and femoral neck. Thalassaemia characteristics were collected from the patients' medical records. Results: A significantly higher sclerostin level (median 565.50 pmol/L) was observed in the transfusion-dependent beta-thalassaemia patients vs. the healthy controls (median 48.65 pmol/L, p < .001). Sclerostin showed significant associations with the Z-scores at the lumbar spine and femoral neck, osteocalcin, beta-cross laps, osteoprotegerin, sRANKL, pretransfusion haemoglobin, liver iron concentration and female gonadal state. Significantly higher levels of sclerostin were observed in splenectomized TDssT patients and in those with fragility fractures. Age, sex, body mass index, disease severity, serum ferritin, cardiac T2* and male gonadal state did not show significant associations with sclerostin. Conclusion: Sclerostin may play a role in the bone pathophysiology of beta-thalassaemia patients and could serve as a marker of severe osteoporosis.KEY MESSAGES Serum sclerostin is more than 10-fold higher in adult patients with transfusion-dependent beta-thalassaemia compared to healthy controls. Serum sclerostin is negatively associated with bone mineral density and the bone synthesis markers and positively with the bone resorption indices. Serum sclerostin is significantly associated with pre-transfusion haemoglobin, liver iron concentration, splenectomy status and fragility fracture events in adult patients with transfusion-dependent beta-thalassaemia. Serum sclerostin could serve as a marker of severe osteoporosis in beta-thalassaemia patients.