Effects of Weight Loss on Portal Pressure in Patients With Overweight/Obesity and Cirrhosis

Overview

Overweight/obesity is increasing both in the general population and in patients with cirrhosis. In compensated patients with cirrhosis increased BMI is a risk factor for clinical decompensation independent of liver function and portal pressure. Nonetheless, patients with cirrhosis and obesity show a progressive increase in portal pressure, which might explain their increased risk of complications. Since obesity is a potentially modifiable risk factor, we designed this proof-of-concept study to assess the effects of weight loss (obtained by 4 months of diet and exercise) on portal pressure in patients with compensated cirrhosis and overweight/obesity.

Overweight and obesity markedly increase the risk of appearance and progression of most chronic diseases, including chronic liver diseases. In the general population obesity is constantly and dramatically raising, and represents a global epidemics. In a study including both European and American patients, our group reported that in patients with compensated cirrhosis overweight/obesity is very frequently observed (55% OW, 15% OB in Spanish patients; \> 50% OB in USA patients), being the figure similar to that of general population. Moreover, this study demonstrated that the increase in body mass index (BMI) is a risk factor for the development of decompensation of cirrhosis, independent of portal pressure and liver function (Berzigotti et al. Hepatology 2011). We also observed that included patients with cirrhosis and obesity showed a significant increase of portal pressure (estimated through hepatic venous pressure gradient measurement-HVPG), which was not found in OW or normal weight patients. This suggests that the mechanism inducing decompensation in obese patients with cirrhosis might be mediated by an increase in portal pressure, even if no data are available in this population to support this hypothesis. It is well known that in obesity the adipose tissue acquires a pro-inflammatory phenotype leading to increased release of IL-1, IL-6 and TNF-alfa and many other pro-fibrogenic cytokines and hormones, which might mediate also an increase in portal pressure. Given these observation, and given the potential reversibility of OW/OB, we hypothesise that weight loss (obtained by diet and exercise) might effectively reduce the HVPG in patients with compensated cirrhosis and OW/OB, so reducing their risk to progression. We designed this proof-of-concept study to confirm this hypothesis.