Increased risk of portal vein thrombosis in patients with cirrhosis due to nonalcoholic steatohepatitis.

Portal vein thrombosis (PVT) is a common complication of cirrhosis sometimes implicated in hepatic decompensation. There are no consistent epidemiologic data to suggest an increased risk of thrombotic complications in nonalcoholic steatohepatitis (NASH); however, research suggests an increased risk of thrombosis. Our aim was to examine the independent association between NASH cirrhosis and PVT in patients who underwent liver transplantation (LT) in a cross-sectional study. Data on all LTs occurring in the United States between January 1, 2003 and December 31, 2012 were obtained from the United Network for Organ Sharing. Multivariable models were constructed to assess the statistical associations and risk factors for the development of PVT. A total of 33,368 patients underwent transplantation. Of these, 2096 (6.3%) had PVT. Of the patients with PVT, 12.0% had NASH. When we compared these patients to a composite of all other causes of cirrhosis, an increased prevalence of PVT was again found, with 10.1% having PVT at the time of transplantation versus 6.0% without NASH (P < 0.001). The strongest risk factor independently associated with a diagnosis of PVT in a multivariable analysis was NASH cirrhosis (odds ratio, 1.55; 95% confidence interval, 1.33-1.81; P < 0.001). NASH cirrhosis appears to predispose a patient to PVT independently of other risk factors. These epidemiological findings provide support for the idea that NASH is a prothrombotic state, and they should lead to more research in treatment and prevention in this population.