Mortality Trends, Outcomes, and Predictors of Portal Vein Thrombosis in Acute Pancreatitis Patients: A Propensity-Matched National Study

Background: Portal vein thrombosis (PVT) is a rare complication of acute pancreatitis (AP) and might be associated with worse outcomes. We aimed to study trends, outcomes, and predictors of PVT in AP patients.

Methods: The National Inpatient Sample database was utilized to identify the adult patients (≥ 18 years) with primary diagnosis of AP from 2004 to 2013 using International Classification of Disease, Ninth Revision. Patients with and without PVT were entered into propensity matching model based on baseline variables. Outcomes were compared between both groups and predictors of PVT in AP were identified.

Results: Among the total of 2,389,337 AP cases, 7046 (0.3%) had associated PVT. The overall mortality of AP decreased throughout the study period (p trend ≤ 0.0001), whereas mortality of AP with PVT remained stable (1-5.7%, p trend = 0.3). After propensity matching, AP patients with PVT patients had significantly higher in-hospital mortality (3.3% vs. 1.2%), AKI (13.4% vs. 7.7%), shock (6.9% vs. 2.5%), and need for mechanical ventilation (9.2% vs. 2.5%) along with mean higher cost of hospitalization and length of stay (p < 0.001 for all). Lower age (Odd ratio [OR] 0.99), female (OR 0.75), and gallstone pancreatitis (OR 0.79) were negative predictors, whereas alcoholic pancreatitis (OR 1.51), cirrhosis (OR 2.19), CCI > 2 (OR 1.81), and chronic pancreatitis (OR 2.28) were positive predictors of PVT (p < 0.001 for all) in AP patients.

Conclusion: PVT in AP is associated with significantly higher risk of death, AKI, shock, and need for mechanical ventilation. Chronic and alcoholic pancreatitis is associated with higher risk of PVT in AP.