Which condition is indicated by cachexia?

Cachexia is a complex syndrome characterized by severe malnutrition and weight loss, often accompanying chronic illnesses such as cancer, heart failure, and AIDS. It involves the loss of muscle mass and fat, leading to a significant decrease in body weight beyond what might be expected from typical starvation. Cachexia is not simply a result of inadequate food intake; it also involves metabolic changes that lead to the body's inability to effectively use nutrients.

This condition often presents with additional symptoms such as fatigue and weakness, but the defining feature is the profound nutritional deficiency and the loss of body mass. Therefore, the indication of cachexia most accurately aligns with severe malnutrition. Conditions like severe hydration, severe infection, and severe fatigue may occur with cachexia, but they are not the primary indicator of this syndrome.