Haemophilia A and B - evaluation of the Swedish prophylactic regimen by magnetic resonance imaging

Introduction: Sweden has been a pioneer in the prophylactic treatment of haemophilia. Magnetic resonance imaging (MRI) can detect small changes in joints and can therefore give an indication of a risk of developing arthropathy.

Aim: To use MRI to evaluate the outcome of the Swedish 'high-dose regimen' and correlate the findings to age, bleeds, joint score and physical activity.

Methods: The study group comprised 48 Swedish male patients, mean age 25 years (range 12-33 years), with severe or moderate haemophilia A or B. Data on the Haemophilia Joint Health Score (HJHS) were available and physical activity was evaluated by a self-reported questionnaire.

Results: MRI score was recorded in 188 joints. Twenty out of 48 patients had a score of ≥1 (range 1-13) in 31 joints of which 3/31 scores were in the knees and 28/31 in the ankles. No correlation was found between the number of recorded bleeds and the MRI score or between HJHS and MRI score. There was no correlation between the physical activity and the number of joint bleeds per se, but a trend (OR 3.0) that those most physically active (19/48; 39.6%), more frequently had an MRI score of ≥1 with an overweight for the right ankle.

Conclusion: The Swedish prophylactic model offers protection against haemophilia joint arthropathy but will still not prevent osteochondral changes in some patients at young age. MRI of the ankles can signal risk of future arthropathy and indicate need to modify the prophylactic regimen.