Joint status of patients with nonsevere hemophilia A

BACKGROUND: Joint bleeding in hemophilia may eventually lead to joint damage. In nonsevere hemophilia, joint bleeds occur infrequently. Currently, knowledge on the joint status of patients with nonsevere hemophilia using objective imaging is limited. OBJECTIVE: To investigate the joint status in patients with nonsevere hemophilia A. METHODS: This cross‐sectional study included patients with nonsevere hemophilia A aged 24–55 years. Joint status was assessed by magnetic resonance imaging (MRI) of the elbows, knees, and ankles and International Prophylaxis Study Group (IPSG) scores were calculated. Lifetime joint bleeding history was collected from medical files. The contribution of factors to joint outcome was explored using multivariable linear regression analysis. RESULTS: In total, 51 patients were included, of whom 19 (37%) had moderate and 32 (63%) had mild hemophilia. Patients had a median age of 43 years (interquartile range [IQR] 32–50), a median factor VIII activity of 10 IU/dl (IQR 4–16) and a median annual joint bleeding rate (AJBR) of 0.0 (IQR 0.0–0.2). Soft‐tissue changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 19%, 71%, and 71% of patients, respectively. Osteochondral changes (IPSG subscore > 0) in the elbows, knees, and ankles were present in 0%, 20%, and 35% of patients, respectively. In 14% of bleed‐free joints, hemosiderin depositions were observed. Age and AJBRs were most strongly associated with the IPSG score. CONCLUSION: This study demonstrates that a substantial proportion of adults with nonsevere hemophilia has joint changes on MRI despite low joint bleeding rates.