[Clinical characteristics and prediction model of early death in severe/very severe aplastic anemia with immunosuppressive therapy]

Objective: Early death (ED) characteristics and predictive factors analysis in patients with severe/very severe aplastic anemia (SAA/VSAA) treated with intensive immunosuppression therapy and establish an ED prediction model. Methods: The clinical data of 232 patients with SAA/VSAA treated with Antithymocyte immunoglobulin (ATG) at the Peking Union Medical College Hospital from August 2003 to August 2021 were collected. The characteristics and causes of ED within 90 days were analyzed retrospectively. Cox proportional hazards model was used to screen the ED risk factors and build a prediction model. Results: Only 19 patients (8.2% ) developed ED with a median time of 24 (3-85) days among the 232 patients with SAA/VSAA who received ATG treatment. The main cause of ED was infection (84.2% ) , followed by cerebral hemorrhage (10.5% ) . Multivariate analysis showed that VSAA (HR=15.359, 95% CI 1.935-121.899, P=0.010) , fungal infection prevention by posaconazole (HR=0.147, 95% CI 0.019-1.133, P=0.066) , lymphocyte count (LYM) ≤ 0.5×10(9)/L (HR=3.386, 95% CI 1.123-10.206, P=0.030) , and PLT ≤ 5×10(9)/L (HR=8.939, 95% CI 1.948-41.019, P=0.005) were ED's independent influencing factors. To build a clinical prediction model, VSAA, fungal infection prevention by posaconazole, LYM ≤ 0.5×10(9)/L, and PLT ≤ 5×10(9)/L were scored with 3, -2, 1, and 2, respectively. The integral model AUC=89.324 (95% CI 80.859-97.789) . The ED risk in patients with a score ≥ 3 was 23.1 (95% CI 5.3-100.2) times that in patients with a score<3. Conclusion: ED caused by infection and cerebral hemorrhage is an important challenge for SAA/VSAA to be treated with ATG. VSAA, LYM ≤ 0.5×10(9)/L, and PLT ≤ 5×10(9)/L patients who did not use posaconazole to prevent fungal infection had a high ED risk.