Kachexi

Kacheksi, or cachexia, is a complex metabolic syndrome characterized by involuntary weight loss, loss of muscle mass, and systemic inflammation that nutrition alone cannot fully correct. It commonly accompanies chronic diseases such as cancer, heart failure, chronic obstructive pulmonary disease, chronic kidney disease, liver disease, and HIV/AIDS, contributing to reduced functional capacity and poorer outcomes.

Pathophysiology: It results from a combination of reduced intake and abnormal metabolism driven by inflammatory cytokines, neurohormonal changes, increased energy expenditure, and accelerated proteolysis and lipolysis. Muscle protein breakdown via the ubiquitin-proteasome pathway, impaired synthesis, and insulin resistance lead to progressive wasting. Cachexia persists despite adequate caloric intake, unlike simple starvation.

Clinical features: Unintentional weight loss, fatigue, weakness, loss of appetite, early satiety, diminished muscle strength, reduced physical activity, and decreased quality of life. Edema and changes in body composition may occur.

Diagnosis: Based on sustained weight loss, typically at least 5% over 6–12 months, with or without a low BMI, plus evidence of reduced muscle mass or function. Diagnosis is clinical and supported by measurements of body composition, grip strength, and functional tests; underlying disease and other causes should be addressed.

Management: Multidisciplinary approach targeting the underlying disease, nutrition, and physical activity. Nutritional support with energy- and protein-dense diets, oral supplements, and counseling are recommended. Exercise, particularly resistance training, helps preserve lean mass. Pharmacologic options (e.g., appetite stimulants or anti-catabolic agents) may be used selectively. Palliative and supportive care are often appropriate.

Prognosis and research: Cachexia is associated with higher mortality, reduced treatment tolerance, and poorer quality of life. Research investigates anti-inflammatory and anabolic strategies, myostatin inhibitors, and other agents, with results varying by disease context.