Clinical outcome of moderate haemophilia compared with severe and mild haemophilia

Summary. Information on outcome and treatment of patients with moderate haemophilia is scarce. In this study, we compared self‐reported burden of disease in moderate haemophilia to severe and mild haemophilia. A nationwide questionnaire on bleeding pattern, treatment, impairment and quality of life was sent to 1567 Dutch patients with haemophilia. Out of 1066 respondents (response rate: 68%), 16% had moderate, 44% severe and 39% mild haemophilia. Median age was 36 years. Although overall outcome in moderate haemophilia was in between severe and mild haemophilia, moderate haemophilia patients did report a substantial burden of disease. The majority of patients with moderate haemophilia (73%) reported bleeds in the previous year; and a considerable proportion of moderate patients reported joint impairment (43%), chronic pain (15%), needed orthopaedic aids (24%) or were unemployed because of disability (27%). Within the group of moderate haemophilia patients, a large variation in bleeding pattern and outcome was observed. A quarter of patients with moderate haemophilia reported a more severe phenotype and intermittent use of prophylaxis. These patients reported frequent bleeding, with a median of eight bleeds per year, including two joint bleeds, and 68% reported joint impairment. In conclusion: Although outcome in moderate haemophilia is generally in between severe and mild haemophilia, moderate haemophilia patients reported a substantial burden of disease, and for more than 25% of patients with moderate haemophilia long term prophylaxis was implemented because of frequent bleeds.