Nutritional therapy in liver cirrhosis: What’s the evidence?

Dietary management of cirrhosis should be implemented early to improve clinical prognosis in patients with liver cirrhosis, according to a recent review published in the Journal of Clinical Gastroenterology.

Liver disease affects more than 10% of the world population, with liver cirrhosis being the primary cause for liver-cause mortality and morbidity. Cirrhosis can cause weakness, nausea, and loss of appetite, often resulting in malnutrition, a serious and highly prevalent feature among cirrhotic patients that is often associated with a poor prognosis. Thus, dietary therapy is integral to the multidisciplinary treatment of liver cirrhosis. Treatment goals include minimizing and correcting malnutrition, preventing progression to liver failure, and managing complications secondary to disease.

“Several guidelines currently exist that incorporate nutritional or dietary recommendations for patients with liver cirrhosis and disease-related complications,” wrote the authors, led by Chu Kion Yao, PhD, Department of Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. “However, these are often based on limited evidence.”

Due to the complex and multifactorial nature of malnutrition, dietary management of liver cirrhosis is complicated and may necessitate a patient-tailored approach to address concerns including protein-energy malnutrition, muscle wasting, adverse effects of fluid retention, and hepatic encephalopathy.

Malnutrition

The prevalence of malnutrition in patients with cirrhosis ranges from 25% to 90%. Contributing factors include nausea, loss of appetite, decreased oral intake of energy and protein, heightened basal metabolic rate, changes in taste receptors, restrictive diets, and unnecessary fasting.

In previous studies, researchers have shown a correlation between malnutrition in the cirrhotic patient and poorer disease outcomes, including a higher incidence and recurrence of complications such as spontaneous bacterial peritonitis, hepatic encephalopathy, variceal bleeding, ascites, and lower survival rates  

Sarcopenia

In these patients, malnutrition can lead to sarcopenia and affects 40% to 70% of patients with advanced cirrhosis. Sarcopenia heightens with overt encephalopathy and is more prevalent than other complications related to progressive cirrhosis.

“Because of the prognostic value of sarcopenia in cirrhosis, careful screening procedures to identify sarcopenia earlier on are critical and will allow for appropriate interventions targeting underlying mechanisms,” the authors wrote. These interventions include promoting increased nitrogen balance, correcting for malnutrition, or reducing ammonia-induced myostatin expression.

On a related note, nutritional assessments in cirrhotic patients are challenging and complicated by the hypervolemia, which can interfere with body weight and body mass index measures, as well as the reduced production or dilution of biomarkers such as albumin.

The authors suggested obtaining bedside anthropometric assessments to evaluate fat and lean muscle mass, such as triceps skin-fold thickness and mid-arm muscle circumference, respectively. These dynamic measures most accurately capture and reflect dietary intervention. Previous studies suggest that patients with liver disease may also benefit from early dietitian screening and management of nutritional risk in combination with physician management.

Caloric intake

One retrospective study highlighted by the reviewers showed that only 45% of energy and 54% of protein requirements are attained by patients hospitalized with liver cirrhosis.

“A continuous energy supply is also needed to provide adequate substrates for energy production, whereas sparing protein utilization,” wrote the authors.

Two studies have shown that energy intake of > 126 kJ/kg/d increased lean body and fat mass and was associated with a positive energy balance.

Previous studies have supported the benefit of increasing meal frequency in cirrhotic patients. One strategy recommended by the authors involves increasing the frequency of meals from three to four per day. The authors pointed out that, although the majority of cirrhotic patients attain adequate nutrition by means of a high-energy and high-protein diet, as well as oral nutrition support, some may require enteral support.

Protein

Adequate protein intake, defined as 1.2 to 1.5 g/kg/d of protein per clinical guidelines, is necessary to maintain or enhance nitrogen balance and prevent further sarcopenia in malnourished cirrhotic patients.

The authors explained that the timing of protein intake is important, with 12 months of nocturnal supplementation associated with increased lean body mass compared with diurnal supplementation.

The investigators also supported the supplemental use of branched-chain amino acids (BCAAs) in patients with advanced cirrhosis.

“There are several proposed benefits of BCAA on nutritional and biochemical parameters, including greater total energy and protein intake, reduction of anorexia, improvements in serum albumin, and increased nitrogen balance,” the authors explained.

Carbohydrates

Unlike dietary protein, few studies have examined the role of dietary carbohydrates in malnutrition interventions. Clinicians should carefully consider the type of carbohydrate utilized in the setting of insulin resistance because nearly all cirrhotic patients are hyperinsulinemic.

“On the basis of the limited data, a carbohydrate-rich diet, particularly one based on low glycemic index sources, does not appear to worsen glycemic control in patients with liver cirrhosis, but could provide an additional source of dietary energy,” the reviewers wrote.

Hepatic encephalopathy

The most germane complication related to diet in the cirrhotic patient is hepatic encephalopathy.

Based on previous research, dietary management of cirrhotic patients should not include protein restriction. Instead, clinicians should take a personalized approach to the patient’s nutritional status and encourage normal protein intake, including both plant- and animal-based proteins, as well as fermentable fiber intake.

Sodium intake

Cirrhotic patients are typically recommended a low-sodium diet to control ascites, edema, and hypertension. However, the clinical benefits of such a diet have been poorly studied, with inconsistent findings.

On the basis of limited data, clinical practice guidelines published by the European Association for the Study of Liver propose a modest restriction in sodium intake in those with cirrhosis (1.8 to 2.8 g/d).

The authors acknowledged that decreasing salt intake in certain cirrhotic patients may be difficult, and that gradual reduction in salt intake over time may be best.

“There is an urgent need to bridge the evidence gap between dietary intervention trials and clinical practice, with a bigger focus on the manipulation of whole diets rather than a large focus on supplementation of protein or BCAA,” concluded the reviewers.