Impact of immune thrombocytopenic purpura on clinical outcomes in patients with acute myocardial infarction

Background: Patients with immune thrombocytopenic purpura (ITP) admitted with acute myocardial infarction (AMI) may be challenging to manage given their increased risk of bleeding complications. There is limited evidence in the literature guiding appropriate interventions in this population. The objective of this study is to determine the difference in clinical outcomes in AMI patients with and without ITP. Methods: Using the United States national inpatient sample database, adults aged ≥18 years, who were hospitalized between 2007 and 2014 for AMI, were identified. Among those, patients with ITP were selected. A propensity-matched cohort analysis was performed. The primary outcome was in-hospital mortality. Secondary outcomes were coronary revascularization procedures, bleeding and cardiovascular complications, and length of stay (LOS). Results: The propensity-matched cohort included 851 ITP and 851 non-ITP hospitalizations for AMI. There was no difference in mortality between ITP and non-ITP patients with AMI (6% vs7.3%, OR:0.81; 95% CI:0.55-1.19; P =.3). When compared to non-ITP patients, ITP patients with AMI underwent fewer revascularization procedures (40.9% vs 45.9%, OR:0.81; 95% CI:0.67-0.98; P =.03), but had a higher use of bare metal stents (15.4% vs 11.3%, OR:1.43; 95% CI:1.08-1.90; P =.01), increased risk of bleeding complications (OR:1.80; CI:1.36-2.38; P <.0001) and increased length of hospital stay (6.14 vs 5.4 days; mean ratio: 1.14; CI:1.05-1.23; P =.002). More cardiovascular complications were observed in patients requiring transfusions. Conclusions: Patients with ITP admitted for AMI had a similar in-hospital mortality risk, but a significantly higher risk of bleeding complications and a longer LOS compared to those without ITP. Further studies are needed to assess optimal management strategies of AMI that minimize complications while improving outcomes in this population.