Although cachexia , a loss of >5% body weight over 12 months, has been reported in about 30% of patients with cancer, many other chronic conditions commonly encountered in our hospitalized patients may also be a culprit. In fact, cachexia is not infrequent in CHF (20%), COPD (20%), kidney failure (40%), or rheumatoid arthritis (10%) (1,2). We also shouldn’t overlook HIV and tuberculosis as a cause.
Cachexia is a multifactorial disease which does not fully reverse with nutritional support. Numerous mediators have been implicated, including cytokines such as tumor-necrosis factor-α, and interleukin [IL]-1 and -6, as well as transforming growth factors such as myostatin and activin A (2).
In patients with CHF, angiotensin II appears to be a key mediator, associated with insulin resistance, depletion of ATP in skeletal muscles, poor appetite, reduction in insulin-like growth factor-1 (IGF-1), and an increase in glucocorticoid and IL-6 levels. All these factors contribute to “cardiac cachexia” through muscle wasting, reduced food intake and lower muscle regeneration.
- Morely JE, Thomas DR, Wilson M-M G. Cachexia: pathophysiology and clinical relevance. Am J Clin Nutr 2006;83:735-43. https://www.ncbi.nlm.nih.gov/pubmed/16600922
- Yoshida T, Delafontaine P. Mechanisms of cachexia in chronic disease states. Am J Med Sci 2015;35:250-256. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4587350/