Reduced bone density among children with severe hemophilia.

Objective: Children with severe hemophilia are at risk for reduced bone mineral density (BMD) because of reduced weight-bearing exercise and hepatitis C infection. Reduced bone density in childhood is a risk factor for osteoporosis in later life.

Study Design: We performed a cross-sectional survey of bone density among 19 children with severe hemophilia, at the Royal Children's Hospital. Results were correlated with findings of blinded objective evaluations of the joints of the lower limb and with hepatitis C status.

Results: The mean lumbar bone mineral apparent density for patients was reduced (0.102 g/cm3), compared with that for control subjects (0.113 g/cm3). The mean areal BMD z score was -0.92, which was significantly reduced, compared with that for control subjects. The difference in bone density was independent of body size. There was a statistically significant relationship between the lumbar BMD z scores and the maximal single joint evaluation scores, but there was no difference based on hepatitis C status.

Conclusions: Our results suggest that children with severe hemophilia have reduced BMD. Patients at risk are those with signs of hemophilic arthropathy. Because osteoporosis may complicate the future treatment of patients with hemophilia, screening of young patients for reduced bone density is recommended.