What is Fatigue Cancer and its Causes, Symptoms & Treatment?

Abida Taher, MD, PhDJuly 10, 2023

Fatigue is normal, but giving in to it is likely to impede your recovery.

“The human body has been designed to resist an infinite number of changes and attacks brought about by its environment. The secret of good health lies in successful adjustment to changing stresses on the body.”
– Harry J. Johnson

It is easy to confuse tiredness and fatigue. Tiredness is short term and happens to all of us, usually after a long day or after physical exertion and you get over it after a good night’s sleep.

Cancer-related fatigue, on the other hand, is daily, persistent lowered energy levels when the body feels weak and worn out and sleep does not help. Between 80% and 90% of people with cancer report having fatigue and even more distressing is the fact that it may not end even when treatment is complete.

This type of fatigue causes problems with even simple physical activities of daily living and can be acute or chronic, sometimes lasting for months to years.

Fatigue, including cancer related fatigue, is less precise, less cause-and-effect.

Causes

Cancer fatigue is one of the most common and profound side effects of cancer and its treatment causes more anguish than pain, nausea, or depression and negatively affects the quality of life of the caregiver as well.

Physical fatigue more often than not leads to mental fatigue and emotional upheaval. It may become impossible to work and the cancer patient may end up taking extended leave or stop working completely.

Job loss can lead to the loss of health insurance causing more trauma. Financial instability causes even more stress and contributes to fatigue.

The warning signs of cancer fatigue include tired eyes with or without blurry vision, arms and legs that feel heavy and too hard to move, whole-body tiredness that causes you to stay in bed for most of the day, lack of energy to do your basic routines, confusion and inability to focus, weakness, lack of motivation, disturbed sleep at night, and increased anxiety and irritability.

Between 80% and 90% of people with cancer report having fatigue and even more distressing is the fact that it may not end even when treatment is complete.

Cancer Fatigue Signs & Symptoms:

The exact cause of cancer fatigue is unknown and most likely multifactorial, related to both the disease process and its treatments including surgery, chemotherapy, radiation therapy, immunotherapy and endocrine therapy.

Fatigue may be a result of anemia due to chemotherapy, from cancer cells competing for nutrients that decrease availability for normal cells, as a side effect of medications, from the stress and mood changes of dealing with a life-threatening illness, from changes in the body’s circadian rhythm, from the release of certain hormones and cytokines as well as other conditions that can happen due to treatment including hypothyroidism.

Whatever the cause, it is important to know that there are no lab tests or x-rays that can diagnose or show your level of fatigue, so it is important for you to tell your caregiver and your health care team if fatigue is an issue.

Many cancer patients do not tell their doctors about cancer related fatigue (CRF) because they assume it is common. It is necessary that you talk to your doctor about this, as well as any other side effects of cancer treatment.

Some of the questions that may help you talk to your cancer care team about fatigue include:

What is the source of my fatigue?
How will I know I have cancer related fatigue or just “tiredness”?
What are the most effective techniques to deal with cancer fatigue?
What is the expected duration of cancer fatigue?

There is no laboratory test to specifically diagnose cancer-related fatigue, but communicating with your doctor about the symptoms you are experiencing can help develop personalized strategies to help you combat fatigue.

Your cancer care team has access to palliative care specialists, trained physical and occupational therapists as well as nutritionists that assist cancer patients in coping with symptoms of cancer such as fatigue, pain, nausea, and anxiety.

Some of the suggested cancer fatigue treatments can include:

Keep moving: Research shows that 30 minutes of activity five days per week or 2.5 hours per week. Some observational studies suggest 3-5 hours of moderate activity per week may help people decrease CRF. Those who have cancer that has spread to bones, people with low blood counts or a fever or those who are at risk of falling should discuss with their healthcare team first before starting any exercise routine.
Mental health support: Behavioral therapy can help you cope with the range of emotions such as depression and/or anxiety that comes with a diagnosis of cancer and treatment related side effects including fatigue. Counseling is an important tool in the arsenal to deal with fatigue. Support networks, both in-person and online, can also be beneficial.
Consult a nutritionist: Increased protein intake may help preserve lean mass and body composition that can help deal with fatigue. Dietary patterns that reduce inflammation, such as the Mediterranean diet and other plant-based diets may also help reduce cancer related fatigue.
Use mind-body techniques: Cognitive behavioral therapy, yoga, acupuncture, guided imagery have been shown to reduce cancer fatigue. Aromatherapy, relaxation, and practices such as qigong and tai chi also aid in decreasing fatigue when used consistently.
Develop good sleeping habits: Keep smartphones and computers out of the bedroom, go to bed at a reasonable time each night, and sleep in a soothing environment to decrease fatigue. If you sleep for more than thirty minutes during the day, you may have problems going to sleep at night. If you have a forthcoming event that needs a great deal of energy, taking a break can certainly be helpful.
Get help: Have relatives and friends run chores, prepare meals, or assist with housekeeping or childcare services. Share your feelings and don’t be afraid to cancel plans if you’re too tired. Taking care of yourself should be your priority as you undergo treatment.
Reduce caffeine intake: Caffeine gives you a brief boost but has the potential to keep you awake at night and therefore, avoiding caffeine at least 6 hours prior to bed time is recommended .
Drink water and eat a wholesome plant based diet: It is critical to drink plenty of water and consume nutritional foods to prevent dehydration which can itself cause fatigue.
Prioritize: Be practical about your abilities. Preserve your energy for the things that truly matter to you.
Talk to your cancer care team about medications that can help with fatigue. Do not start any herbal supplements or vitamins without consulting with your cancer doctor.

Cancer related fatigue can impact your physical, psychological and emotional well-being. It helps to remember that fatigue is normal during cancer treatment and does not mean your cancer is getting worse or that your treatment is not working.

As a cancer patient, talking with your cancer care team and coming up with a strategic plan that can help you deal with fatigue is the best step you can take to preserve your physical energy and mental health through treatment and beyond.