Associations between intracranial haemorrhage and prescribed prophylaxis in a large cohort of haemophilia patients in the United States

P>Intracranial haemorrhage (ICH) is the most serious type of bleeding for patients with haemophilia. Prior published reports regarding ICH predate the widespread provision of prophylaxis. Our study objectives were to determine risk factors for ICH and whether prophylaxis reduces ICH occurrence. We performed a nested case-control study of persons with haemophilia, >= 2 years of age enrolled in the Centers for Disease Control and Prevention Universal Data Collection project. Of 10 262 patients 199 (1 center dot 9%) experienced an ICH for an incidence rate of 390/105 patient years. Head trauma was reported in 44% (88/199). ICH mortality was 19 center dot 6% (39/199). Significant risk factors for ICH included a high titre inhibitor [odds ratio (OR) = 4 center dot 01, 95% confidence interval (2 center dot 40-6 center dot 71)], prior ICH [OR = 3 center dot 62 (2 center dot 66-4 center dot 92)] and severe haemophilia [OR = 3 center dot 25 (2 center dot 01-5 center dot 25)]. Prophylaxis was associated with a significant risk reduction for ICH occurrence in patients with severe haemophilia who were negative for human immunodeficiency virus or an inhibitor, with an OR of 0 center dot 52 (0 center dot 34-0 center dot 81) and 0 center dot 50 (0 center dot 32-0 center dot 77) respectively. The most significant risk factors for ICH included the presence of an inhibitor, prior ICH, severity of haemophilia and reported head trauma. This is the first study to demonstrate that prescribed prophylaxis conferred a protective effect against ICH in patients with uncomplicated severe disease.