Splenectomy and the incidence of venous thromboembolism and sepsis in patients with autoimmune hemolytic anemia

Introduction: The impact of splenectomy on venous thrombosis (VTE), abdominal thrombosis (abVTE) and sepsis in autoimmune hemolytic anemia (AIHA) is unclear. Methods: Using the California Discharge Dataset 1991-2014, 4756 AIHA patients were identified. Cumulative incidences (CI) of VTE, abVTE, and sepsis were determined in patients with and without splenectomy. Using propensity score matching adjusted for competing risk of death, the association between VTE, abVTE and sepsis with splenectomy was determined. Results: In those without splenectomy, the CIs of VTE, abVTE, and sepsis were 1.4%, 0.2%, and 4.3% respectively, compared to 4.4%, 3.0% and 6.7% with splenectomy. Splenectomy was associated with increased risk for VTE in immediate (HR 2.66, CI 1.36-5.23) and late (HR 3.29, CI 2.10-5.16) post-operative periods. AbVTE was increased in immediate post-operative period (HR 34.11, CI 4.93-236.11). Sepsis was only increased in late postoperative period (HR 2.20, CI 1.75-2.77). In multivariate models, older age, having > 1 comorbidity and having VTE, abVTE, and sepsis were associated with increased mortality. Splenectomy was not associated with increased mortality. Discussion: Splenectomy in AIHA was associated with significant early thrombotic risk and long-term morbidity. Future research should evaluate the role of splenectomy in AIHA patients, and potential long-term thrombotic and antibiotic prophylaxis.