Trends and outcomes of venous thromboembolism in adult hospitalizations with acute myeloid leukemia: analysis of nationwide inpatient sample from 2010 to 2014

Background: Venous thromboembolism (VTE) occurs frequently in acute myeloid leukemia (AML) patients. There are no population-based studies from the United States (U.S.) analyzing this association. The study aims to analyze the trends, predictors of mortality, and outcomes of VTE in AML patients.
Methods: We analyzed the publicly available Nationwide Inpatient Sample (NIS) for years 2010–2014. Hospitalizations due to AML were identified by previously validated International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes as the primary diagnosis. VTE was identified by ICD-9-CM codes as secondary diagnosis. Hospitalizations with age less than 18 years of age were excluded. The trends and outcomes were determined using Chi-squared (χ2) test and multivariate regression models.
Results: From 2010 to 2014, there were 313,282 hospitalizations with a primary diagnosis of AML and 1,633 hospitalizations (0.1%) had VTE as a concurrent diagnosis. There was a significant increase in the proportion of AML hospitalizations with VTE from 0.47% in 2010 to 0.56% in 2014 (P = 0.014). Multivariable regression analysis showed that the odds of in-hospital mortality were not higher in AML hospitalizations with VTE (odds ratio [OR] 1.11; 95% confidence interval [CI] 0.81–1.52; P = 0.5) than those without VTE. Age group above 84 years carried the highest risk of mortality (OR 3.20; 95% CI 2.77–3.70; P < 0.0001) in AML-VTE patients. Black (OR 1.23; 95% CI 1.13–1.35; P < 0.0001) and uninsured patients (OR 1.50; 95% CI 1.31–1.73; P < 0.0001) were at significantly higher odds of in-hospital mortality amongst the AML-VTE hospitalizations.
Conclusion: The proportion of AML hospitalizations with VTE continues to rise in the U.S. After adjusting for confounders, increasing age, Black race, and lack of insurance were found to have higher risk of in-hospital mortality in the AML-VTE cohort. The odds of in-hospital mortality in AML hospitalizations with VTE are not higher than those without VTE.