Venous thromboembolism as a trigger for acute cardiac decompensation during cancer hospitalizations: A National Inpatient Sample analysis, 2018–2022.

e23099 Background: Venous thromboembolism (VTE) is a common complication of malignancy, but its role as a trigger for acute cardiac and hemodynamic decompensation during hospitalization is poorly defined. Most studies emphasize VTE incidence rather than downstream inpatient severity. This study evaluated whether pulmonary embolism (PE) and deep vein thrombosis (DVT) are associated with disproportionate inpatient deterioration in hospitalized patients with cancer. Methods: We conducted a serial cross-sectional analysis of adult hospitalizations with a principal diagnosis of malignancy in the 2018–2022 Healthcare Cost and Utilization Project National Inpatient Sample. VTE was identified using any-diagnosis ICD-10-CM codes for PE (I26*) and DVT (I82*) and categorized as no VTE, DVT only, PE only, or PE with concurrent DVT. Outcomes included All Patient Refined Diagnosis Related Group (APR-DRG) severity, extreme severity (APR-DRG level 4), in-hospital mortality, shock, mechanical ventilation, length of stay (LOS), and hospitalization cost. Survey-weighted multivariable regression adjusted for demographics, payer, income quartile, admission type, cancer subtype, hospital characteristics, and year. Results: Among 961,848 unweighted cancer hospitalizations representing 4,809,239 admissions nationally, VTE occurred in 5.51 percent, including PE only in 2.00 percent, DVT only in 3.85 percent, and PE with DVT in 0.52 percent. Inpatient severity increased stepwise across VTE phenotypes. Mean APR-DRG severity increased from 2.51 with no VTE to 3.35 with DVT only, 3.63 with PE only, and 3.80 with PE plus DVT. Extreme severity occurred in 3.09 percent without VTE versus 8.49 percent, 11.68 percent, and 15.20 percent, respectively. Mortality increased from 4.01 percent to 9.67 percent, 13.76 percent, and 12.69 percent, with higher rates of shock and mechanical ventilation. LOS and costs were highest among PE plus DVT admissions. After adjustment, PE only was independently associated with extreme severity (OR 8.39, 95% CI 7.64 to 9.22), shock (OR 2.81, 95% CI 2.55 to 3.09), mechanical ventilation (OR 2.98, 95% CI 2.77 to 3.21), and mortality (OR 2.95, 95% CI 2.80 to 3.12). PE plus DVT conferred the highest risk of shock (OR 4.14, 95% CI 3.69 to 4.64) and extreme severity (OR 18.85, 95% CI 16.07 to 22.10). Conclusions: During cancer-related hospitalizations, venous thromboembolism, particularly pulmonary embolism, functions as a major trigger for acute cardiac and hemodynamic decompensation rather than an isolated thrombotic event. These findings highlight VTE as a key driver of inpatient severity, critical care utilization, and mortality in oncology populations.