Cachexia & Anorexia Nervosa

What is Cachexia?

Cachexia, sometimes called “wasting syndrome,” is a metabolic disorder associated with substantial weight loss. It is frequently defined as “a multifactorial syndrome defined by an ongoing loss of skeletal muscle mass (with or without loss of fat mass) that can be partially but not entirely reversed by conventional nutritional support." It is not just a condition of inadequate nutritional intake but is frequently due to long-standing or end stage conditions associated with inflammation, metabolic changes, and anorexia. The pro-inflammatory state and metabolic changes create an imbalance between anabolism, or those metabolic processes that synthesize tissue and create growth, and catabolism, or those metabolic processes that break down tissue and create atrophy.  Cachexia is also usually associated with a reduced quality of life and high mortality. Additional symptoms of cachexia can include:

• Muscle wasting
• Reduced strength
• Loss of body fat
• Weakness, frailty, and fatigue
• Malnourished appearance
• Anemia
• Low albumin
• Anorexia (loss of appetite)

Anorexia, or loss of appetite, is frequently associated with cachexia, and is a completely different entity from anorexia nervosa and other eating disorders. Anorexia can occur for multiple reasons, including:

• Changes in taste or smell
• Mental health changes, including depression
• The underlying medical condition causing the cachexia, which is often associated with a pro-inflammatory state and hypermetabolic state
• Medications
• Dietary changes recommended to treat the underlying medical condition

Medical conditions associated with cachexia include:

• Cancer
• HIV/AIDS
• Chronic obstructive pulmonary disorder (COPD)
• Congestive heart failure
• Chronic kidney disease
• Cystic fibrosis
• Rheumatoid arthritis and other autoimmune diseases
• Celiac disease
• Crohn’s disease
• Mycobacterium avium complex (MAC) infection
• Many others

Research has found that many of the conditions mentioned above can be associated not only with disordered eating but also eating such as anorexia nervosa. Anorexia nervosa (AN) is a life-threatening mental health disorder wherein people restrict food to a great deal with a goal of achieving a very thin body. With AN, there is an abnormal focus on body image, and a large number of medical complications and severe symptoms that develop due to the underlying malnutrition. Unlike other psychiatric disorders, every organ system is adversely affected by AN and no body system is protected from the ravages of starvation.

There are two subtypes of anorexia nervosa: 

• The restricting type (AN-R) is associated with the previously mentioned symptoms and behaviors and does not include regular bingeing of food.
• The binge-eating/purging type (AN-BP) is marked by bingeing and purging behaviors such as self-induced vomiting or the misuse of diuretics or laxatives, or both.

The serious medical consequences of prolonged starvation and malnutrition make anorexia nervosa the deadliest psychiatric disorder next to deaths from opioids. Patients with anorexia nervosa are five times more likely to die prematurely. Although the immune system is dysregulated in anorexia nervosa and the body is in a state of catabolism, the immune system changes in AN do not lead to low albumin levels seen in the many pro-inflammatory conditions listed above. Indeed, low albumin levels should suggest the need to search out additional medical concerns, such as those listed above, that may be contributing to weight loss and cachexia.

Treatment for Cachexia 

Treatment for the above conditions includes not only nutritional rehabilitation but also treatment of the underlying condition leading to the weight loss as well as mental health support. ACUTE can manage not only the potential complications associated with weight restoration, including the feared refeeding syndrome, but we have the expertise to manage the other medical comorbidities and diseases mentioned above. These conditions are frequently associated with a hyper-metabolic state, meaning the amount of nutrition required to successfully weight restore can often be very high. Therefore, without appropriate treatment of the underlying medical condition, weight restoration becomes very difficult. Our multifactorial team consisting of medical doctors, dieticians, psychologists, psychiatrists, and other clinical support staff can help start that treatment journey.

People diagnosed with cancer or other serious illnesses may develop cachexia and anorexia. When signs of cachexia and anorexia are observed, early intervention offers the best chance of survival. Medications, dietary interventions, exercise programs and supplements may help to improve quality of life and alleviate symptoms. 

Resources

• Eckart A, Struja T, and Kutz A, et al. Relationship of nutritional status, inflammation, and serum albumin levels during acute illness: A prospective study. Am J Med 2020;133:713-22.
• Fearon K, Strasser F, Anker SD, et al. Definition and classification of cancer cachexia: an international consensus. The Lancet Oncology 2011;12(5):489-95.
• Gibson D and Mehler PS. Anorexia nervosa and the immune system—A narrative review. Journal of Clinical Medicine 2019;8:1915.
• Mehler PS and Koutsavlis A. Anorexia nervosa, albumin, and inflammation: Letter to the Editor. The American Journal of Medicine 2021;134(6):e401.
• National Cancer Institute. (2011, November 11). Tackling the Conundrum of Cachexia in Cancer. National Cancer Institute. Retrieved October 13, 2021.
• Quick VM, Byrd-Bredbenner C, Neumark-Sztainer D. Chronic illness and disordered eating: A discussion of the literature. Adv Nutr 2013;4:277-86.

Last Reviewed: December 2023 by Dennis Gibson, MD, FACP, CEDS