Bone disease in patients with haemophilia. What is true?

摘要

To the editor: Ghoshy et al. in their recent review in European Journal of Haematology (1) tried to present data about the prevalence of low bone mineral density (BMD) in patients with haemophilia A and B and analyse the pathophysiology of this entity proposing appropriate management. The authors report data of small studies and refer mainly to the association of low BMD with hepatitis C (HCV) and human immunodeficiency virus (HIV) infections and their treatment (interferon-alpha, antiretroviral therapy). They also refer to the possible role of vitamin K and the interaction between factor VIII-von Willebrand and receptor activator of nuclear factor-kappaB (RANK) ligand (RANKL), in the induction of osteoclasto-genesis (1). In the largest study conducted so far, we found an increased prevalence of bone disease in haemophiliacs of Northern Greece (26.9%), compared with apparently healthy age- and sex-matched controls, a prevalence that was lower than previously reported. Except for the lower prevalence of severe haemophilia in our cohort, this difference is mainly attributed to the fact that in all the previous studies, T-scores were used for all patients irrespectively of their age, instead of using them only for patients > 50 yr old and Z-scores for those < 50 yr old, based on the criteria for the definition of osteoporosis in males by the International Society of Clinical Densitometry (ISCD). According to ISCD, when Z-scores are <-2 SD, BMD is defined as 'below the expected range for age' and not 'osteoporosis'. In a similar way, a BMD with Z-score >-2 and <-l SD, in a patient <50 yr old, is considered normal and not 'osteopenia' (2). If T-scores were used, the prevalence of low BMD in our series would have been about 50% and about 74% in those with severe haemophilia (3).