Postpartum acquired hemophilia A (AHA) was significantly associated with longer time to bleeding response (TTBR) and bleeding response (BR) was significantly associated with longer overall survival (OS), researchers reported in a study published in Haemophilia.
AHA is a rare autoimmune disease in which the patient develops inhibitory autoantibodies against circulating factor VIII (FVIII:C). It occurs in patients without a personal or family history of bleeding and is typically diagnosed in elderly adults. Typical symptoms include spontaneous bleeding, as well as bleeding from trauma or surgery. In rare cases, bleeding is mild and can be managed conservatively. However, in the majority of cases, bleeding is severe enough to cause intracranial hemorrhage or large intramuscular or retroperitoneal hematomas, all of which can be life-threatening.
Patients are usually treated with immunosuppressant therapy (IST), but the time to response (TTR) can sometimes be too long, rendering the treatment ineffective when bleeding occurs. Thus, a key goal is to improve the TTR of the treatment while avoiding infection-related mortality due to the suppression of the immune system.
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Researchers set out to study the prognostic variables for TTBR, BR, and OS. The definition of best response (BR) was a complete response (CR) or partial response (PR) measured any time after treatment initiation and maintained until final observation. CR and PR were defined as follows:
- CR: FVIII:C >50 IU/dL with undetectable inhibitors, an absence of bleeding, and the stopping of IST.
- PR: FVIII:C >50 IU/dL with persistent inhibitors without active bleeding after stopping any hemostatic drug for more than 24 hours.
The researchers conducted a single-center, retrospective study involving 61 patients with AHA seen at their institution. A total of 56 patients underwent hemostatic therapy, and 60 underwent first-line IST therapy. Taken together, the BR rates obtained at the final observation (a median period of 70 days) were: CR: 64% and PR: 8%. Researchers then looked into a few factors to study their prognostic impacts on BR, TTBR, and 12-month OS. Among the factors investigated were age, sex, hemoglobin levels, and types of therapy.
Researchers found that none of these factors had any statistically significant influence on BR. However, they did discover that TTBR was significantly higher in postpartum AHA than in other forms of AHA, including idiopathic AHA. BR was found to be the only independent predictor of 12-month OS.
The authors stated, “Notably, the 12-months OS was 100% in cases associated with postpartum and autoimmune diseases, 83% in idiopathic AHA, and 63% in cases with concomitant malignancies.”
Porrazzo M, Baldacci E, Ferretti A, et al. Single centre experience on acquired haemophilia A patients: diagnosis, clinical management and analysis of factors predictive of response and outcome. Haemophilia. Published online August 11, 2021. doi:10.1111/hae.14395