Cachexia
Cachexia is a cytokine-driven metabolic wasting syndrome of ongoing skeletal muscle loss, with or without fat loss, that complicates cancer, heart failure, COPD, chronic kidney disease, and chronic infection and cannot be reversed by nutrition alone. Diagnosis rests on greater than 5% weight loss over 12 months in the setting of chronic illness plus supporting features such as reduced strength, anorexia, and elevated inflammatory markers, and management combines treatment of the underlying disease with multimodal nutrition, resistance exercise, and appetite stimulants.
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What this article covers
- Overview
Definition: a complex metabolic wasting syndrome of ongoing loss of skeletal muscle mass, with or without loss of fat mass, driven by an underlying chronic illness and systemic inflammation rather than by inadequate food intake alone.
- Epidemiology
Prevalence rises with disease burden and stage: most common and most severe in advanced cancer, particularly pancreatic and gastric cancer, and in advanced heart failure, COPD, and chronic kidney disease.
- Risk factors
Active malignancy, especially gastrointestinal, lung, and pancreatic cancer: the tumor drives a systemic proinflammatory state independent of tumor burden alone.
- Pathophysiology
Chronic illness triggers systemic inflammation: the underlying tumor or organ-failure state releases proinflammatory cytokines, chiefly TNF-alpha, IL-1, and IL-6, into the circulation.
- Clinical features
Involuntary weight loss: loss of more than 5% of body weight over the preceding 6 to 12 months in a patient with known or suspected chronic illness is the hallmark presenting feature.
- Differential diagnosis
Marasmus (starvation): pure calorie-deficient malnutrition without significant systemic inflammation; muscle and fat are lost proportionally, and unlike cachexia it reverses substantially with adequate feeding alone.
- Diagnosis
Establish with consensus clinical criteria: cachexia is diagnosed when weight loss exceeds 5% of body weight over the preceding 12 months (or BMI is below 20 kg/m²) in the setting of an underlying…
- Management
Treat the underlying disease first: optimize cancer-directed therapy, heart failure guideline-directed medical therapy, COPD pharmacotherapy, dialysis adequacy, or antiretroviral therapy for HIV…
- Complications
Progressive functional decline: muscle loss reduces mobility, increases fall risk, and impairs activities of daily living.
- Prognosis
Prognosis tracks the underlying disease and the degree of muscle loss: cachexia is an independent adverse prognostic marker across cancer, heart failure, COPD, and chronic kidney disease, worsening…
- Prevention
Screen weight trend at every visit in patients with cancer, heart failure, COPD, chronic kidney disease, or chronic infection, and flag a loss of 5% or more of body weight over 6 to 12 months for evaluation.
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