The cause of malnutrition among those with liver disease is multifactorial. Nutritional status is influenced by inadequacy of diet (including iatrogenic restrictions), malabsorption (biliary and sometimes pancreatic), anorexia, nausea and vomiting, dysguesia, gastroparesis, alcohol toxicity and altered nutrient metabolism .
It is theorized that energy expenditure may be elevated in patients with liver failure, thus contributing to a malnourished state. However, in one study comparing energy expenditure in 74 patients with cirrhosis and 9 healthy controls, the energy expenditures were not different between the groups except when the patients were stratified based on the level of malnutrition. Those patients with cirrhosis who were considered malnourished had a lower basal energy expenditure than did the controls . Even then, if the energy expenditures were evaluated according to BCM, there were no differences. Refer to the section on calorie needs for a full review on energy expenditure and liver disease.
Ascites also influences the degree of malnutrition. The physical presence of ascites can restrict stomach volume and induce early satiety ; thus, satiety is often relieved by paracentesis. On the other hand, drainage of ascitic fluid also results in losses of protein and further malnutrition. Campillo et al.  showed that anthropometric measurements and dietary intake paralleled the degree of ascites. Midarm muscle circumference <5th percentile was present in 49% of patients with no ascites, 49.1% of patients with mild ascites and 65.5% of patients with severe ascites (p < 0.05). Likewise, tricep skinfold measurements <5th percentile occurred in 30.4% of patients without ascites, 40.5% of those with mild ascites and 48.3% of those with tense ascites (p = 0.02). Reduced calorie and protein intakes were also correlated with tense ascites. Moreover, Santolaria et al.  showed that patients with ascites were more significantly malnourished (based on anthropometric measurements) than patients without ascites.
When ascites is relieved, nutritional status can improve. A small study showed that patients (n = 10) who underwent a trans-intrahepatic portal shunt (TIPS) procedure for ascites management experienced an increase in dry weight, total body nitrogen and resting energy expenditure (REE) 3 and 12 months after the procedure . There was also a significant increase in total body fat 12 months post-TIPS. There was, however, no change in total body potassium, muscle force or Child-Pugh score underscoring the difficulty in reaccumulating lean body mass in the presence of liver dysfunction. Similar findings were reported in a study in which 21 patients were evaluated before and 6 and 12 months after a TIPS procedure . Body cell mass (BCM) based on total body potassium counting, bioelectrical impedance and anthropometry improved 6 and 12 months after TIPS.
Psychosocial factors also influence nutritional status. Santolaria et al.  studied 181 hospitalized alcoholic men. Malnutrition was related to intensity of alcohol intake, development of social or family problems, irregularity of eating habits and presence of cirrhosis and ascites. The "skid row" alcoholic was found to be the most nutritionally impaired in the group with 73% of those patients having a body mass index (BMI) < 20kg/m2, 55% having a tricep skinfold measurement <50th percentile and 75% of the group displaying a midarm muscle area measurement <50th percentile.
Was this article helpful?
Studies show obesity may soon overtake tobacco as the leading cause of death in America. Are you ready to drop those extra pounds you've been carrying around? Awesome. Let's start off with a couple positive don't. You don't need to jump on a diet craze and you don't need to start exercising for hours each day.