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.