Osteoporosis and associated risk factors in patients with severe hemophilia A: a case-control study from China

INTRODUCTION: People with hemophilia risk osteoporosis more than healthy people, which may be related to specific factors. METHODS: This case-control study included 53 patients with severe hemophilia type A and 49 healthy participants. Dual-energy X-ray absorptiometry (DXA) was used to determine bone mineral density (BMD). Collected information on age, body mass index (BMI), number of joint arthropathies, functional independence score in hemophilia (FISH), bone turnover markers, antibodies, treatment modalities. Identified independent risk factors for osteoporosis. RESULTS: The BMD of the femoral neck (0.80 g/cm(2)vs.0.97 g/cm(2)), ward’s triangle (0.62 g/cm(2)vs.0.83 g/cm(2)), tuberosity (0.63 g/cm(2)vs.0.80 g/cm(2)) and hip (0.80 g/cm(2)vs.0.98 g/ cm(2)) in the case group were significantly lower than those in the control group, all of which were P < 0.001. However, there was no significant difference in the overall BMD of lumbar spine(L1-L4) (1.07 g / cm(2)vs. 1.11 g / cm(2)). The frequency of osteoporosis in the case group was 41.51%. BMI and FISH score were considered as independent risk factors for BMD decrease. CONCLUSION: The BMD of patients with severe hemophilia A is much lower than that of healthy population, and this difference is mainly reflected in the hip. The clear influencing factors were low BMI and functional independence decrease. Osteoclast was active while osteoblast activity was not enhanced synchronously, which may be the pathological mechanism of BMD decrease.