Cachexia is a complex syndrome characterized by progressive weight loss, muscle wasting, weakness, and a decline in overall physical functioning. Common symptoms of cachexia include:

Unintentional and severe weight loss, often involving both muscle mass and fat.

Loss of appetite (anorexia) and reduced food intake.

Fatigue, weakness, and decreased stamina.

Muscle wasting, leading to a loss of strength and mobility.

Changes in body composition, with a significant decrease in lean body mass.

Cachexia is also known as "wasting syndrome" or "cancer cachexia" when it occurs in the context of cancer. It can also be associated with other chronic conditions like chronic kidney disease, heart failure, chronic obstructive pulmonary disease (COPD), and HIV/AIDS.

In the context of cancer, cachexia refers to the multifactorial syndrome characterized by the severe wasting of muscle and adipose tissue, along with systemic inflammation. It is estimated that up to 80% of advanced cancer patients may experience cachexia, particularly in aggressive cancers such as pancreatic, lung, or gastrointestinal cancers. Cachexia in cancer negatively impacts the patient's quality of life, response to treatment, and overall survival.

Cachexia and weight loss are related but distinct terms:

Weight loss: Weight loss refers to a reduction in body weight, which can occur due to various factors such as reduced calorie intake, increased physical activity, or certain medical conditions. Weight loss can be intentional (e.g., through diet and exercise) or unintentional (e.g., due to an underlying illness).

Cachexia: Cachexia, on the other hand, is a complex metabolic syndrome characterized by more than just weight loss. It involves the loss of both muscle mass and fat tissue, along with systemic inflammation, metabolic abnormalities, and reduced physical function. Cachexia is typically associated with chronic illnesses like cancer and is more severe and difficult to reverse compared to simple weight loss.

In summary, cachexia encompasses severe weight loss, muscle wasting, and overall decline in physical functioning, often observed in advanced stages of chronic illnesses like cancer. While weight loss is a general term referring to a reduction in body weight, cachexia goes beyond simple weight loss and involves complex metabolic changes and profound impact on a person's well-being.

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