RESUMO
OBJECTIVES: To explore the long-term joint outcomes of low-dose prophylaxis in Chinese children with severe haemophilia A and to analyse their related factors. METHODS: We retrospectively analysed follow-up data from 21 severe haemophilia A children on regular low-dose prophylaxis for 6-10 years. We used International Prophylaxis Study Group magnetic resonance imaging score (IPSG MRI score), Hemophilia Joint Health Score (HJHS), number of target joints, and Hemophilia-Specific Quality of Life Index (Haemo-QoL) to evaluate joint outcomes. Factors associated with these outcomes were evaluated by statistical analysis. RESULTS: (1) The children were 1.75 to 17 years age at prophylaxis initiation. Median prophylactic factor VIII dose was 22.9 IU/kg per week. (2) At the end of follow-up: (a) The total IPSG MRI scores were 2-24 with 90.5% children exhibiting moderate to severe joint involvement (score 7-24); (b) The HJHS ranged 2-27, with 0-10 for 46.7% children and >10 for 53.3% children. There was a positive correlation between the MRI score and HJHS (p < .05); (c) Compared to their on-demand treatment period before prophylaxis, target joints numbers decreased, and no child needed auxiliary devices to walk; (d) Joint outcomes were positively correlated with the age at initiation of low-dose prophylaxis (p < .05) and negatively correlated with the treatment dose. CONCLUSION: Long-term low-dose prophylaxis had positive effect on joint outcomes compared with on-demand treatment. However, a certain degree of joint damage remained in all children indicating the need for improving the current strategy of low-dose prophylaxis.
