Abstract Rationale Heparin-induced thrombocytopenia (HIT) is a rare but serious complication of heparin therapy that can lead to paradoxical thrombosis. In patients with acute pulmonary embolism (APE), the coexistence of HIT may worsen the hypercoagulable state, increasing the risk of poor outcomes. While few studies have suggested this association, large-scale data on the incidence of HIT in APE admissions and factors linked to mortality remain limited. Methods We analyzed data from the National Inpatient Sample (NIS) for adult patients (≥18 years) admitted with APE between 2016 and 2022. HIT cases were identified using ICD-10 diagnostic codes, and the incidence rate was calculated per 100,000 APE admissions. Mortality rates were compared between HIT and non-HIT patients. Multivariable logistic regression analysis was performed to identify factors associated with mortality among HIT patients. COVID-19 cases were excluded throughout this study, and appropriate adjustments for the database model were made for national estimates. Results We identified 1,298,609 APE cases, of which 3,885 developed HIT, corresponding to an incidence of 299 per 100,000 PE admissions. Patients with HIT were slightly younger (mean age: 62.15 years vs. 63.42 years in non-HIT patients, p = 0.014) and had a marginally higherCharlson Comorbidity Index (CCI) score (mean: 2.61 vs. 2.08, p 0.01).HIT was associated with significantly increased mortality, with 6.06% in HIT patients compared to 3.19% of non-HIT patients (aOR 1.764, 95% CI 1.282-2.428, p 0.01). Among HIT patients, key factors associated with higher mortality risk included liver cirrhosis (aOR 4.143, 95% CI 2.015 - 8.516, p 0.01) and coagulopathy (aOR 2.476, 95% CI 1.120 - 5.473, p = 0.025). Advanced age was also linked to increased mortality (mean age of deceased patients: 66.49 years vs. 61.92 years in survivors, aOR 1.042, 95% CI 1.008-1.077, p = 0.014). Conversely, patients on long-term anticoagulation demonstrated reduced mortality risk (aOR 0.280, 95% CI 0.084, 0.933, p = 0.038).No statistically significant associations with mortality were found for race, sex, insurance type, year of admission, or various other comorbidities (Table 1). Length of hospital stay was comparable between HIT patients who survived and those who died (mean: 12.70 vs. 12.10 days, p = 0.723). Conclusion HIT occurred at an incidence of approximately 299 per 100,000 APE admissions and was associated with nearly double the mortality risk compared to non-HIT patients. Advanced age, liver cirrhosis, and coagulopathy significantly increased mortality, whereas long-term anticoagulation decreased the risk. These findings emphasize the need for early detection and appropriate management of HIT in patients with APE. This abstract is funded by: None
Dhaliwal et al. (Fri,) studied this question.