Cortical and trabecular bone changes in men with haemophilia: findings from The Haemophilia Osteoporosis Registry (THOR) — ASN Events
  1. Schedule
  2. ANZBMS Plenary Posters Session
  3. Cortical and trabecular bone changes in men with haemophilia: findings from The Haemophilia Osteoporosis Registry (THOR)

Cortical and trabecular bone changes in men with haemophilia: findings from The Haemophilia Osteoporosis Registry (THOR) (#106)

Ayse Zengin 1 , Vanessa Gan 1 , Huyen Tran 2 , Peter R Ebeling 1
  1. Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Clayton, VIC, Australia
  2. Haemophilia Treatment Centre, Alfred Hospital, Melbourne, VIC, Australia

Background: Haemophilia A is a rare X-linked bleeding disorder caused by factor VIII deficiency. Most people with haemophilia (PWH) experience haemarthrosis, leading to progressive joint damage and poor bone health. Osteoporosis affects 27% of PWH, with a further 43% having osteopenia, and fragility fracture risk is 4.4-fold higher than in age- and sex-matched controls.

 

Purpose: To investigate differences in trabecular and cortical bone variables at the radius and tibia in PWH compared with controls over one year.

 

Methods: Eighty-seven men (76 controls, 11 PWH; ≥18 years) underwent HR-pQCT scans at baseline and after one-year at the 4% and 30% radius and tibia. Outcomes included total volumetric bone mineral density (vBMD), cortical vBMD, trabecular vBMD, trabecular number, and cortical thickness. Mixed-effects models assessed whether changes over time differed between groups using a time×group interaction term, reporting β-coefficients. Models were adjusted for age, weight, and height.

 

Results: After adjustment, PWH showed consistently, and substantially lower vBMD and impaired microarchitecture compared with controls at both skeletal sites. At the radius, PWH had lower total vBMD (β= –57.3 mg/cm³, p< 0.001), trabecular vBMD (β= –47.8 mg/cm³, p<0.001), trabecular number (β= –0.24 mm⁻¹, p<0.001), and cortical thickness (β= –0.30 mm, p = 0.026). Similar or greater deficits were observed at the tibia, including reduced total vBMD (β= –54.8 mg/cm³, p<0.001), trabecular vBMD (β= –62.5 mg/cm³, p<0.001), trabecular number (β = –0.40 mm⁻¹, p<0.001), and cortical thickness (β= –1.50 mm, p<0.001). No significant changes over time were detected in either group and all time×group interaction terms were non-significant (p>0.57), indicating similar longitudinal trajectories.

 

Conclusion: PWH exhibit markedly lower volumetric bone density and impaired microarchitectural integrity than controls, with large deficits across all HR-pQCT variables. Over one year, bone variables remained stable in both groups. These results underscore the need for routine bone health screening and targeted interventions for PWH.