Obesity is not associated with an increased risk of portal vein thrombosis in cirrhotic patients

AIM: To determine the impact of obesity on development of portal vein thrombosis in cirrhotic patients. BACKGROUND: Cirrhosis is a known risk factor for portal vein thrombosis (PVT). Evidence also points to obesity as being a risk factor for venous thromboembolism. Limited information is available on how obesity impacts the development of PVT in cirrhotic patients. METHODS: This was a retrospective cohort study using the 2013 National Inpatient Sample. Patients older than 18 years with an ICD-9 CM code for any diagnosis of liver cirrhosis were included. There was no exclusion criteria. The primary outcome was the impact of obesity on development of PVT. Obesity was also sub-classified according to body-mass index (BMI). Secondary outcomes were in-hospital mortality, ICU admission, shock, TPN use, and resource utilization. Odds ratios (OR) and means were adjusted for age, gender, and ethnicity. RESULTS: We included 69,934 obese cirrhotics of which, 1,125 developed PVT (mean age 59 years, 35% female). Overall in-hospital mortality rates were 9% (11% with PVT vs 5% without PVT). On multivariate analysis, obesity was not associated with a significantly different adjusted OR for development of PVT compared to non-obese. When stratifying by obesity subtype, class 1 obesity was associated with increased odds of PVT (OR: 1.45, 95%CI: 1.06-1.96, p=0.02), while class 3 obesity was associated with a decreased odds of PVT (OR: 0.72, 95%CI: 0.58-0.88, p<0.01) compared to non-obese. CONCLUSION: Obesity is not associated with increased odds of PVT.