Cachexia (Wasting Syndrome)

What cachexia means

The word comes from Greek words for "bad condition". Cachexia is a recognized syndrome, not just "being thin". The commonly used research definition is unintended weight loss of at least 5 percent in 12 months or less in someone with a chronic illness, together with signs such as reduced muscle strength, fatigue, poor appetite, low muscle mass, or blood markers of inflammation or anemia.

For cancer, experts describe three stages:

Cachexia vs malnutrition and other wasting

People can have more than one. Older adults with chronic illness often have cachexia, sarcopenia and poor intake together. Severe childhood starvation is a different condition, marasmus.

Why it happens

Chronic diseases, and some tumors directly, release inflammatory messengers (cytokines such as TNF-alpha and IL-6) and other factors that:

• break down muscle protein faster than it can be rebuilt
• increase resting energy use
• reduce appetite through effects on the brain
• disturb how fat, sugar and protein are handled

Other contributors include nausea, taste changes, mouth sores, swallowing difficulty, constipation, depression, pain, breathlessness during eating, and side effects of treatments such as chemotherapy.

Conditions that cause cachexia

• Cancer: affects up to about half of people with advanced cancer; most common in pancreatic, stomach, esophageal, lung and head and neck cancers.
• Heart failure ("cardiac cachexia")
• COPD: the work of breathing burns energy and inflammation drives muscle loss.
• Chronic kidney disease, especially on dialysis.
• HIV, especially untreated, and tuberculosis.
• Rheumatoid arthritis and other chronic inflammatory diseases.
• Advanced liver disease.

Signs and symptoms

• Unintended weight loss, often noticed through loose clothes or rings
• Visible muscle wasting, especially at the temples, shoulders, thighs and hands
• Weakness, tiredness and reduced ability to do daily tasks
• Loss of appetite and feeling full quickly (loss of appetite)
• Low mood and reduced quality of life
• Swelling in the legs in some people, which can mask weight loss on the scales

How it is assessed

A doctor or dietitian will review your weight over time, what you eat, symptoms affecting eating, and how active you are. Assessment may include:

• weight and BMI, with calf or upper-arm circumference
• grip strength and walking speed
• CT scans already done for cancer, which can measure muscle mass
• blood tests: albumin, C-reactive protein, blood count, and tests for other causes of weight loss such as thyroid disease or diabetes

Treatment and management

Cachexia is easiest to treat early. The best approach combines several measures:

Treating the underlying disease

Controlling the cancer, optimizing heart failure treatment, or starting HIV treatment can stabilize or reverse weight loss.

Nutrition support

• Small, frequent, high-energy and high-protein meals and snacks
• Oral nutritional supplements (prescribed drinks)
• Treating barriers to eating: nausea, mouth sores, constipation, dry mouth, pain and depression
• Tube feeding in selected people, for example with head and neck cancer, when the gut works but swallowing does not

Exercise

Resistance (strength) exercise and walking, adjusted to ability and supervised by a physical therapist, help preserve muscle and function.

Medicines

• Progestins (megestrol acetate) and short courses of corticosteroids can boost appetite and weight, mostly as fat or fluid, and have side effects such as blood clots.
• Low-dose olanzapine is used in some people with advanced cancer to improve appetite.
• Newer drugs targeting appetite and inflammation are being studied.

These do not reliably rebuild muscle, so they are used alongside nutrition and exercise.

In advanced illness

In refractory cachexia, the focus shifts to comfort: eating for pleasure, relieving symptoms and supporting families. Not wanting to eat is a natural part of advanced illness, and forcing food can cause distress. Palliative care teams can help.

Frequently asked questions

What is cachexia?

Cachexia is a wasting syndrome caused by serious chronic illness such as cancer, heart failure or COPD. The disease triggers inflammation and metabolic changes that break down muscle and fat and reduce appetite, so people lose weight and strength even when they try to eat.

What is the difference between cachexia and malnutrition?

Malnutrition is caused by not getting enough nutrients and usually improves with adequate food. Cachexia is driven by the disease itself, with inflammation and muscle breakdown, so extra calories alone only partly help. The two often occur together in people with serious illness.

Can cachexia be reversed?

Early cachexia can sometimes be stabilized or partly reversed by treating the underlying disease and combining nutrition support, exercise and appetite treatment. In advanced, refractory cachexia, reversal is unlikely and care focuses on comfort and quality of life.

What are the first signs of cachexia?

Early signs include unintended weight loss, loose clothing, poor appetite, feeling full quickly, tiredness and weakness, and thinning of the muscles in the arms, legs and temples. In someone with cancer or another chronic illness, these should prompt a nutrition assessment.

How long can someone live with cachexia?

It depends on the underlying disease and how advanced it is. Cachexia itself is linked with shorter survival and reduced tolerance of cancer treatment. Refractory cachexia in advanced cancer usually means a life expectancy of weeks to a few months.