Joint health and treatment modalities in Nordic patients with moderate haemophilia A and B – The MoHem study

Introduction: The prevalence of arthropathy in moderate haemophilia A (MHA) and B (MHB) is not well known. Aim: We evaluated joint health in Nordic patients in relation to their treatment modality. Methods: A cross-sectional, multicentre study covering MHA and MHB in Sweden, Finland and Norway. Arthropathy was evaluated by ultrasound (HEAD-US) and Haemophilia Joint Health Score (HJHS). Results: We report on 145 patients: median age 28 years (IQR 13-52) and 61% MHA. Baseline factor VIII/factor IX activity (FVIII/FIX:C) was 2 IU/dL (median) (IQR 2-4): lower for MHB (2 IU/dL, IQR 1-2) than MHA (3 IU/dL, IQR 2-4) (P <.01). Eighty-five per cent of MHA and 73% MHB had a history of haemarthrosis (P =.07). Age at first joint bleed was lower for MHA (5 years [median], IQR 3-7) than MHB (7 years, IQR 5-12) (P =.01). Thirty-eight per cent received prophylaxis, started at median 10 years of age (IQR 4-24). Median joint bleeds and serious other bleeds during the last 12 months were both zero (IQR 0-1). Total HEAD-US captured 0/48 points (median) (IQR 0-2) and HJHS 4/120 points (IQR 1-10) with strong correlation between them (r =.72). FVIII/FIX:C ≤ 3 IU/dL was associated with higher HJHS (P =.04). Fifteen per cent had undergone orthopaedic surgery. Conclusion: The current joint health in Nordic moderate haemophilia patients was rather good, but a subgroup had severe arthropathy. FVIII/FIX:C ≤ 3 IU/dL and MHA were associated with a more severe bleeding phenotype. We suggest primary prophylaxis to all patients with FVIII/FIX:C ≤ 3 IU/dL.