Cancer Fatigue: It's Not Just Tiredness

Fatigue and tiredness often get confused. Tiredness happens to everyone; it is a feeling expected after certain activities or at the end of a long day and is usually resolved by a good night’s sleep. Fatigue, however, is a daily lack of energy; the entire body is tired and sleep does not help. In addition, fatigue causes problems with usual functioning and can be acute (lasting up to a month) or chronic (lasting more than a month).^1-3

Cancer fatigue (CF) is one of the most common adverse effects of both the disease process and the treatment. The exact cause is unknown and varies among patients. CF cannot be predicted by tumor type, treatment, or stage of the illness, and levels of severity vary among patients and can have a profoundly negative effect on their quality of life (QOL).¹

Causes

Cancer changes the body in ways that can cause fatigue, such as causing the release of cytokines or altering hormones.⁴ Tumor cells also compete for nutrition at the expense of normal cells, and some cancers increase the body’s need for energy, weaken muscle, and damage essential organs.⁴

Treatments such as chemotherapy (80% of patients experience CF), radiation therapy (90% of patients experience CF),⁵ surgery, bone marrow transplantation, and biologic therapy are all known to cause fatigue. But the feeling doesn’t end when treatment does. Fatigue may continue while the body tries to repair damage to healthy cells and tissues that were destroyed as collateral damage of the targeted cancer cells.⁴

Diagnosis

A physician will gather a fatigue history by asking several questions (see table). He or she may also record sleep and nutritional histories and ask the patient about stress levels and emotions.⁴ A review of medications and pain management is also helpful. There also may be blood tests and x-rays. Blood tests may indicate anemia and can help rule out other contributing factors, such as hypothyroidism. X-rays can help determine if the cancer has worsened or spread.^3,4

Management

The best way to manage CF is to treat the underlying cause. Because this is usually unknown, treatment should be individualized. A variety of measures exists to help combat CF. Exercise can require a substantial amount of effort, but may result is less fatigue, and study results have shown that patients who exercise are less depressed and less tired, and sleep better than patients who don’t exercise.⁶ Practicing relaxation techniques, limiting caffeine, and maintaining good sleep hygiene also help improve sleep. Other techniques include massage, yoga, and mindful exercises (similar to meditation), such as focusing on breathing and awakening of senses.

Nutrition is often an issue in patients with cancer due to treatment-related mouth sores, nausea, vomiting, and anorexia. Patients should ensure they are consuming appropriate amounts of fluids for cell function; proteins for cell growth, repair, and immunity; and other nutrients, such as fats, carbohydrates, vitamins, and minerals. in order to prevent CF. This will help patients feel better, be better able to tolerate side effects from cancer treatment, maintain body weight, avoid illness, maintain energy and strength, and heal and recover faster. Referral to a dietician or nutritionist may be beneficial.⁶

Psychosocial measures, such as counselling, joining a support group, or learning stress-management techniques may reduce stress, anxiety, and depression, thereby strengthening the patient’s coping ability, elevating their mood, and restoring energy.⁶ Conserving energy and resting are important in battling CF, as patients need to be realistic about their limitations.

Prioritizing activities helps to conserve energy, but requires planning ahead, delegating tasks, combining activities, simplifying details, and pacing one’s self. The most important tasks should be undertaken when the body is at its best.⁷

Treatment

Treating the underlying causes of fatigue is the first step in treatment. Hypothyroidism should be treated with a thyroid hormone, while depression should be treated with an antidepressant that does not cause fatigue. If the patient is already taking such an antidepressant, consider changing the dosage or drug.

Hematopoietics can be used to treat anemia in patients with CF. Study results have shown an increase in hemoglobin concentrations correlated to improvements in energy level, activity level, and overall QOL.⁸ However, study results have shown mixed reviews on using psychostimulants: whereas methylphenidate did not show significant improvement of CF over placebo, dexmethylphenidate did.⁸

Corticosteroids have been reported to improve QOL and reduce pain and CF in patients with metastatic cancer. Steroids may be most helpful to patients in the terminal phases of advanced cancer with CF.⁸

Patients treated with L-carnitine reported improvement in fatigue and QOL measures.⁸ L-carnitine is important for processing longchain fatty acids and energy production, but chemotherapy lowers its levels in the blood.

Lastly, modafinil has shown positive effects such as improved wakefulness and decreased fatigue severity in patients suffering from CF.⁸

Dr. Kenny earned her doctoral degree from the University of Colorado Health Sciences Center. She has 20+ years’ experience as a community pharmacist and works as a clinical medical writer based out of Colorado Springs, Colorado. Dr. Kenny is also the Colorado Education Director for the Rocky Mountain Chapter of the American Medical Writer’s Association and a regular contributor to Pharmacy Times®.

References:

• Coping with fatigue. MedicineNet website. medicinenet.com/script/main/art.asp?articlekey=42457. Accessed October 11, 2016.
• Fatigue and cancer fatigue. Chemocare website. http://chemocare.com/chemotherapy/side-effects/fatigue-and-cancer.aspx. Accessed October 11, 2016.
• Fatigue. Cancer.Net website. cancer.net/navigating-cancer-care/side-effects/fatigue. Accessed October 11, 2016.
• Cancer. Mayo Clinic website. mayoclinic.org/diseases-conditions/cancer/in-depth/cancer-fatigue/art-20047709. Accessed October 10, 2016.
• Hofman M, Ryan JL, Figueroa-Moseley CD, Jean-Pierre P, Morrow GR. Cancer-related fatigue: the scale of the problem. Oncologist. 2007;12(suppl 1):4-10.
• Fighting cancer fatigue. National Comprehensive Cancer Network website. nccn.org/patients/resources/life_with_cancer/fatigue.aspx. Accessed October 15, 2016.
• Cancer-related fatigue. WebMD website. webmd.com/cancer/fatigue-cancer-related. Accessed October 10, 2016.
• Carroll JK, Kohli S, Mustian KM, Roscoe JA, Morrow GR. Pharmacologic treatment of cancer-related fatigue. Oncologist. 2007;12(suppl 1):43-51.