Patient outcomes in myeloproliferative neoplasm-related thrombosis: Insights from the National Inpatient Sample

Philadelphia-negative myeloproliferative neoplasms (MPNs) – polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) – often present with thrombosis. We aimed to determine the inpatient mortality, cost of care, and length-of-stay among individuals with Philadelphia-negative MPNs who had arterial or venous thrombosis associated with admission versus those who were admitted for non-thrombosis-related events. Using ICD-10M coding, we identified 7,128,770 patients from the National Inpatient Sample (NIS) database who were hospitalized in 2016. 31,302 patients had a diagnosis of a Philadelphia-negative MPN. Mortality, length-of-stay, and cost of care were compared between patients who had thrombosis included among the top three diagnoses and those who were admitted for other reasons. Chi-squared test for categorical variables and t-test for continuous variables were used to compare baseline characteristics. Final multivariable models were constructed to determine predictors of outcomes. Inpatient mortality was significantly higher among individuals with Philadelphia-negative MPN who had thrombosis associated with admission as compared to those who were hospitalized for other reasons (5.7% versus 3.1%, P