Anorexia-cachexia - the condition and its causes

Anorexia-cachexia is a progressive wasting condition that commonly affects people in the advanced stages of diseases such as cancer and acquired immune deficiency syndrome (AIDS). It is described by loss of appetite (anorexia) and loss of weight (cachexia).The word “anorexia” comes from the Greek word orexis (meaning “appetite”), literally translating to “without appetite”. The word “cachexia” is derived from the Greek words kakos (meaning “bad”) and hexis (meaning “condition”). Anorexia-cachexia is a complex, lifethreatening condition in which there is early satiety, loss of appetite, chronic nausea, involuntary weight loss, tissue wasting, loss of muscle, severe fatigue, weakness, poor physical performance and poor immune function. It is a significant cause of psychological distress to patients and to their families, friends and carers. Anorexia-cachexia occurs in several chronic, end-stage conditions including cancer, AIDS, chronic obstructive pulmonary disease, heart, renal and hepatic failure, inflammatory bowel disease (eg, Crohn’s disease), cystic fibrosis, rheumatoid arthritis and bacterial and parasitic diseases. This condition affects nearly half of cancer patients. However, severe cachexia develops in most patients with advanced cancer or advanced AIDS. At the time of diagnosis, about 80 per cent of patients with upper gastrointestinal cancers and 60 per cent of patients with lung cancer have substantial weight loss. In pancreatic cancer, 85 per cent of patients develop cachexia. In general, patients with haematological malignancies or breast cancer do not tend to have substantial weight loss, but most other solid tumours are associated with a high frequency of cachexia. Cachexia is more common in children and older people and becomes more severe as disease progresses. Overall, more than 80 per cent of patients with cancer or AIDS develop cachexia before they die. In more than 20 per cent of patients, cachexia is the main cause of death.