Malnutrition, a subacute or chronic nutritional condition, arises from insufficient (or excessive) food intake and/or inflammation, leading to compromised body composition and reduced bodily functions, adversely affecting clinical outcomes and prognosis. Given the liver’s central role in metabolizing glucose, proteins, and fats, patients with ongoing liver damage, especially cirrhosis, commonly suffer from malnutrition. Studies indicate that 40% to 90% of hospitalized patients with liver disease experience malnutrition. It is an independent predictor of mortality in cirrhosis patients and is closely linked to complications like ascites, hepatic encephalopathy, infections, and recent findings also suggest connections with reduced quality of life, sleep disorders, micronutrient deficiencies, and frailty.
In recent years, leading international nutrition/liver disease organizations and societies have released targeted guidelines and consensus statements. The European Association for the Study of the Liver (EASL) in 2018 published the “Clinical Practice Guidelines on Nutrition in Chronic Liver Disease,” the European Society for Clinical Nutrition and Metabolism (ESPEN) in 2020 released the “Clinical Nutrition in Liver Disease,” and the American Association for the Study of Liver Diseases (AASLD) in 2021 issued the Practice Guidance “Malnutrition, Frailty, and Sarcopenia in Patients with Cirrhosis.” These publications underscore the clinical significance of malnutrition risk screening, nutritional assessment, and intervention treatment. Accordingly, in 2018, the Chinese Society of Hepatology and the Chinese Society of Gastroenterology all of the Chinese Medical Association (CMA) released China’s first “Clinical Nutrition Guidelines for End-Stage Liver Disease,” significantly advancing standardized diagnosis and treatment in this field and promoting the concept of nutritional therapy.
Considering the rapid progression of related research and the swift accumulation of knowledge, Dr. Chao Sun of the Department of Gastroenterology at Tianjin Medical University General Hospital, reflecting on his research experiences and extensive literature review, presented several thoughts at the end of 2023. He encourages colleagues in this field to join him in embracing new breakthroughs in 2024.
1．The Necessity and New Challenges of Nutritional Screening
Nutritional screening for inpatient and outpatient cirrhosis patients is essential for subsequent nutritional assessment and treatment. Despite awareness of malnutrition’s significant impact on various adverse outcomes, it’s often overlooked due to clinical complexities and lack of specialized knowledge. Institutions are encouraged to use specific scales suitable for end-stage liver disease, like the RFH-NPT for rapid screening and high sensitivity. Additionally, tools like NRS 2002 are also recommended.
The recent prevalence of metabolic diseases like obesity and type 2 diabetes has altered the spectrum of liver diseases, leading to a “double burden of malnutrition” as defined by the WHO, where undernutrition and obesity coexist. It has also been reported that metabolic associated fatty liver disease has become a significant cause of cirrhosis, but nutritional screening in these patients is often neglected.
2. The Possibility of Uniform Nutritional Assessment Standards
Previous studies, using different assessment tools and methods for cirrhosis patients at various stages, reported significant differences in malnutrition rates, complicating subsequent nutritional treatment. In order to establish a standardized diagnosis of malnutrition across different patient populations and clinical Settings, and given the current lack of universally accepted consensus, the Global Leadership Initiative on Malnutrition (GLIM) convened major clinical nutrition societies to discuss and collaborate on this issue.
GLIM proposes a stepped diagnostic approach, combining phenotypic criteria (involuntary weight loss, low BMI, and muscle mass reduction) with at least one etiological criterion (reduced food intake/absorption and inflammation) for malnutrition diagnosis. GLIM’s framework has been found valuable in identifying patients with poor physiological conditions and severe disease, predicting short-term adverse prognosis, and it may become widely adopted and promoted in clinical practice.
3. The Significance of Sarcopenia in Diagnosing Malnutrition
Sarcopenia, characterized by systemic and progressive loss of skeletal muscle mass and function, is linked to significantly increased risks of adverse outcomes. A 2022 meta-analysis revealed that cirrhosis patients with sarcopenia have a doubled mortality rate. The European Working Group on Sarcopenia in Older People 2 (EWGSOP2) recently revised its consensus on sarcopenia’s definition/diagnosis, emphasizing decreased muscle strength followed by reduced muscle quantity or quality. Considering the similar internal drivers of sarcopenia and malnutrition, including inadequate nutrition, lack of physical activity, aging, and specific disease burdens, muscle mass reduction is a diagnostic criterion for both GLIM-defined malnutrition and EWGSOP2-defined sarcopenia.
Sarcopenia focuses only on the specific assessment of muscle abnormalities, whereas malnutrition has a broader meaning. Both may arise at the same time and have a synergistic effect. The research by our team found the incidence of malnutrition in hospitalized patients with cirrhosis is higher compared to sarcopenia, so screening and diagnosis of malnutrition should be focused first in daily clinicians. A detailed examination for sarcopenia is required if it suggests significant muscle quantity/strength loss.
4. The Relationship Between Protein-Energy Malnutrition and Micronutrient eficiency
Essential micronutrients are proven to participate in various physiological activities, maintaining homeostasis and involving growth, metabolism, immune regulation, anti-oxidative stress, and anti-aging. Hence, their deficiency can lead to developmental delays or diseases. The liver plays a crucial role in the absorption, transportation, distribution, excretion, and utilization of micronutrients. Chronic liver damage inevitably leads to micronutrient excess or deficiency, further exacerbating chronic liver disease progression. While cirrhosis patients often experience varying degrees of malnutrition, the relationship between micronutrients and overall nutritional status, specifically protein-energy malnutrition, remains unclear.
Recent studies have comprehensively analyzed micronutrient deficiencies in decompensated cirrhosis patients, indicating prevalent zinc deficiency closely related to underlying liver dysfunction. Research also shows that high-risk patients have significantly lower serum zinc compared to those with low/medium nutritional risk, suggesting that continuous zinc deficiency adversely impacts ammonia metabolism and protein metabolism. This synergistic effect, along with severe hypoalbuminemia and hyperammonemia, precipitates early high nutritional risk.
The research by our team found that over half of the patients with decompensated cirrhosis experience a decline in health-related quality of life, with malnutrition being a significant independent risk factor. Thus, there’s a call for clinical doctors and nurses to pay more attention to the management of patients with cirrhosis. In fact, compared to the management of other chronic diseases such as chronic pulmonary disease, heart failure, hypertension, and diabetes, the management of chronic liver disease still urgently needs improvement.
On one hand, nurses can enhance patient education, thereby promoting patients’ ability for self-care, preventing complications, and improving their quality of life. On the other hand, exploring multidisciplinary treatment models (MDT) and nutrition support teams (NST) involving clinical physicians, dietitians, head nurses, and clinical pharmacists is a promising solution for improving the prognosis of these patients.
Expert Profile
Dr. Chao Sun
Associate Chief Physician, graduated from Peking University Health Science Center with a Bachelor’s degree, holds a Doctorate in Medicine/Science from Tianjin Medical University, and was a researcher at Hyogo College of Medicine in Japan.
TAG: insights; malnutrition; cirrhosis
