Abstract 4135095: Outcomes of Atrial Fibrillation Patients with Thrombocytopenia: Insights From a Nationwide Database

Background: While anticoagulation is crucial for atrial fibrillation (AF) patients to prevent ischemic events, those with thrombocytopenia have a potential increased risk of bleeding. This study examines the outcomes of hospitalized AF patients with thrombocytopenia. Methods: The National Inpatient Sample (NIS) from 2016-2020 was analyzed to identify adult patients with AF and thrombocytopenia (using the proper ICD-10 codes). Multivariate logistic and regression analyses were performed after adjusting for multiple patient and hospital confounders to compare outcomes between patients with and without thrombocytopenia. The primary outcome was all-cause inpatient mortality. Secondary outcomes included major bleeding (defined as gastrointestinal, intracranial, pulmonary, or unspecified bleeding), hypovolemic shock, packed red blood cell (pRBC) transfusion, ischemic stroke, length of stay (LOS), and total charges. Results: Among 2,016,244 AF admissions, 75,545 patients (3.75%) had thrombocytopenia. Thrombocytopenia was associated with increased inpatient mortality (adjusted odds ratio [aOR] 2.47, 95% CI 2.21-2.77, p < 0.001). Thrombocytopenia was also associated with increased risk of major bleeding (aOR 1.99, 95% CI 1.8-2.19, p < 0.001), hypovolemic shock (aOR 3.11, 95% CI 2.29-4.24, p < 0.001), pRBC transfusion (aOR 3.07, 95% CI 2.8-3.37, p < 0.001). There was no significant difference in ischemic stroke risk (aOR 0.67, 95% CI 0.37-1.21, p < 0.19) but thrombocytopenia was associated with longer LOS (aMD 1.5 days, 95% CI 1.41-1.59, p < 0.001) and higher total charges (aMD $16,508, 95% CI 14,805-18,211, p < 0.001). Conclusions: Thrombocytopenia in hospitalized AF patients is associated with increased mortality, bleeding risk, and healthcare costs, with no clear impact on ischemic stroke. These findings highlight the need for careful risk-benefit assessment and individualized management strategies for this vulnerable patient population.