Long-term joint outcomes in adolescents with moderate or severe haemophilia A

INTRODUCTION: Favourable joint outcomes are expected with modern haemophilia A (HA) management. Evaluation of long-term treatment outcomes is hampered by the delay between bleeding episodes during childhood and resulting joint outcomes in adulthood.

AIM: To measure the long-term joint health of adolescents with moderate and severe HA, according to severity and inhibitor status.

METHODS: Pilot cross-sectional study of five European PedNet centres in moderate and severe HA patients aged 10-19 years. Structured assessment of joint status by physical examination (HJHS) and ultrasound (HEAD-US).

RESULTS: In total, 141 HA patients were evaluable, 100 without inhibitors (81 severe, 19 moderate HA), and 41 severe HA with current/past inhibitors. On physical examination, 12/81 (15%) of severe HA without inhibitors, 3/19 (16%) of moderate HA, and 13/41 (32%) of severe HA patients with inhibitors exhibited joint abnormalities. Inhibitor persistence, longer inhibitor duration, and a high peak inhibitor level were associated with impaired joint health. Ultrasound showed joint damage (bone or cartilage) in 13/49 (27%) of severe HA without inhibitors, 1/12 (8%) of moderate HA, and 10/28 (36%) of severe HA patients with inhibitors. A discordant ankle evaluation by ultrasound versus physical examination was present in 53/169 joints (31%).

CONCLUSIONS: Most adolescents with severe or moderate HA show favourable joint health. Future research with combined ultrasound and/or MRI is needed to better understand joint outcomes in the remaining patients. Patents with inhibitors showed a two-fold increased proportion with joint deterioration. Ultrasound paired with physical examination increases sensitivity for detection of joint damage.