Cancer-related fatigue is common in cancer patients. Fatigue is often confused with tiredness. Tiredness happens to everyone — it’s a feeling you expect after certain activities or at the end of the day. Usually, you know why you are tired and a good night’s sleep solves the problem.
Fatigue is a daily lack of energy; an unusual or excessive whole-body tiredness not relieved by sleep. It can be acute (lasting a month or less) or chronic (lasting from one month to six months or longer). Fatigue can prevent you from functioning normally and impacts your quality of life.
Cancer-related fatigue (CRF) is one of the most common side effects of cancer and its treatment. It is not predictable by tumor type, treatment or stage of illness. Usually, it comes on suddenly, does not result from activity or exertion, and is not relieved by rest or sleep. It may continue even after treatment is complete.
What Causes CRF?
The exact reason for CRF is unknown, but it may be related to the disease process or its treatments.
The following cancer treatments are commonly associated with fatigue:
- Chemotherapy . Any chemotherapy drug may cause fatigue. Patients frequently experience fatigue after several weeks of chemotherapy, but this varies among patients. In some patients, fatigue lasts a few days, while others say the problem persists throughout the course of treatment and even after the treatment is complete.
- Radiation therapy . Radiation therapy can cause cumulative fatigue (fatigue that increases over time). This can occur regardless of the treatment site. Fatigue usually lasts from three to four weeks after treatment stops but can continue for up to two to three months.
- Hormone therapy can cause fatigue by depriving the body of estrogen. It can last throughout the course of treatment or longer.
- Bone marrow transplant . This aggressive form of treatment can cause fatigue that lasts up to one year.
- Biological therapy . Interferons and interleukins are cytokines, natural cell proteins that are normally released by white blood cells in response to infection. In high amounts, these cytokines can lead to persistent fatigue.
- Combination therapy. More than one cancer treatment at the same time or one after the other also increases the chances of developing fatigue.
What Other Factors Contribute To Fatigue?
Other factors which may contribute to fatigue include:
- Tumor-induced “hypermetabolic” state. Tumor cells compete for nutrients, often at the expense of normal cells. In addition to fatigue, weight loss and decreased appetite are common effects.
- Decreased nutrition from the side effects of treatments (such as nausea, vomiting, mouth sores, taste changes, heartburn, or diarrhea) can cause fatigue.
- Cancer treatments can cause reduced blood cell counts that can lead to anemia, a blood disorder that occurs when there is not enough hemoglobin, a substance in red blood cells that enables the blood to transport oxygen through the body. When the blood cannot transport enough oxygen to the body, fatigue can result.
- If the thyroid gland is under-active, metabolism may slow down so that the body does not burn food fast enough to provide adequate energy. This is a common condition in general, but may also happen after radiation therapy to the lymph nodes in the neck.
- Medicines used to treat side effects such as nausea, pain, depression, anxiety and seizures can cause fatigue.
- Less physical activity and mobility problems can lead to fatigue in older people. Younger people in treatment sometimes overexert themselves and bring on fatigue.
- Hormonal changes related to medicine, including cancer medicines, can cause fatigue.
- Chronic, severe pain increases fatigue.
- Stress can worsen feelings of fatigue. Stress can result from dealing with the disease and its “unknowns,” as well as from worrying about daily accomplishments or trying to meet the expectations of others. Fatigue often results when patients try to maintain their normal daily routines and activities during treatment. Modifying your activities can help conserve energy.
Depression and fatigue often go hand-in-hand, but it may not be clear which started first. One way to sort this out is to try to understand your depressed feelings and how they affect your life. If you are depressed all the time, were depressed before your cancer diagnosis, or are preoccupied with feeling worthless and useless, you may need treatment for depression.
What Can I Do To Combat Fatigue?
The best way to combat fatigue is to treat the underlying medical cause. Unfortunately, the exact cause is often unknown or there may be multiple causes.
There are some medical treatments that may help improve fatigue caused by hypothyroidism or anemia. Other causes of fatigue must be managed on an individual basis.
- Evaluate your level of energy. Think of your personal energy stores as a “bank.” Deposits and withdrawals have to be made over the course of the day or the week to balance energy conservation, restoration and expenditure. Keep a diary for one week to identify the time of day when you are either most fatigued or have the most energy. Note what you think may be contributing factors.
- Be alert to your personal warning signs of fatigue. Fatigue warning signs may include tired eyes; tired legs; whole-body tiredness; stiff shoulders; decreased energy or a lack of energy; inability to concentrate; weakness or malaise; boredom or lack of motivation; sleepiness; increased irritability; and nervousness, anxiety or impatience.
- Plan ahead and organize your work.
- Change where you store items to reduce trips or reaching.
- Delegate tasks when possible.
- Combine activities and simplify details.
- Schedule rest.
- Balance periods of rest and work.
- Rest before you become fatigued — frequent, short rests are beneficial.
- Pace yourself.
- A moderate pace is better than rushing through activities.
- Reduce sudden or prolonged strains.
- Alternate sitting and standing.
- Practice proper body mechanics.
- When sitting, use a chair with good back support. Sit up with your back straight and your shoulders back.
- Adjust the level of your work — work without bending over.
- When bending to lift something, bend your knees and use your leg muscles to lift, not your back. Do not bend forward at the waist with your knees straight.
- Carry several small loads instead of one large one, or use a cart.
- Limit work that requires reaching over your head.
- Use long-handled tools.
- Store items lower.
- Limit work that increases muscle tension (isometric work).
- Breathe evenly, do not hold your breath.
- Wear comfortable clothes to allow for free and easy breathing.
- Identify effects of your environment.
- Avoid extremes of temperature.
- Eliminate smoke or harmful fumes.
- Avoid long, hot showers or baths.
- Prioritize your activities.
- Decide what activities are important to you, and what could be delegated.
- Use your energy on important tasks.
What About Nutrition?
Cancer-related fatigue is often made worse if you are not eating enough or if you are not eating the right foods. Maintaining good nutrition can help you feel better and have more energy. Here are some strategies to help improve your nutritional intake:
- Meet your basic calorie needs. The estimated calorie needs for someone with cancer is 15 calories per pound of weight if your weight has been stable. Add 500 calories per day if you have lost weight. Example: A person who weighs 150 pounds needs about 2,250 calories per day to maintain his or her weight.
- Get plenty of protein. Protein rebuilds and repairs damaged (and normally aging) body tissue. The recommended daily allowance of protein for adult women is 46 grams per day and for adult men is 56 grams per day. The best sources of protein include foods from the dairy group (8 ounces milk = 8 grams protein) and meats (meat, fish or poultry = 7 grams of protein per ounce).
- Drink plenty of fluids. A minimum of eight cups of fluid per day will prevent dehydration. Fluids can include juice, milk, broth, milkshakes, gelatin and other beverages. Of course, water is fine, too. Beverages containing caffeine do NOT count. Keep in mind that you’ll need more fluids if you have treatment side effects such as vomiting or diarrhea.
- Make sure you are getting enough vitamins. Take a vitamin supplement if you are not sure you are getting enough nutrients. A recommended supplement would be a multivitamin that provides at least 100 percent of the recommended daily allowances (RDA) for most nutrients. Note: Vitamin supplements do not provide calories, which are essential for energy production. So vitamins cannot substitute for adequate food intake.
- Make an appointment with a dietitian. A registered dietitian can provide suggestions to work around any eating problems that may be interfering with proper nutrition (such as early feeling of fullness, swallowing difficulty, or taste changes). A dietitian can also suggest ways to maximize calories and include proteins in smaller amounts of food (such as powdered milk, instant breakfast drinks and other commercial supplements or food additives).
What About Exercise?
Decreased physical activity, which may be the result of illness or of treatment, can lead to tiredness and lack of energy. Scientists have found that even healthy athletes forced to spend extended periods in bed or sitting in chairs develop feelings of anxiety, depression, weakness, fatigue, and nausea.
Regular, moderate exercise can decrease these feelings, help you stay active and increase your energy. Even during cancer therapy, it is often possible to continue exercising. Here are some guidelines to keep in mind.
- Check with your health-care provider before beginning an exercise program.
- A good exercise program starts slowly, allowing your body time to adjust.
- Keep a regular exercise schedule. Perform moderate-intensity exercise at least 150 minutes a week.
- The right kind of exercise never makes you feel sore, stiff or exhausted. If you experience soreness, stiffness, exhaustion or feel out of breath as a result of your exercise, you are overdoing it.
- Most exercises are safe, as long as you exercise with caution and you don’t overdo it. The safest and most productive activities are swimming, brisk walking, indoor stationary cycling and low impact aerobics (taught by a certified instructor). These activities carry little risk of injury and benefit your entire body.
How Can I Manage My Stress?
Managing stress can play an important role in combating fatigue. Here are some suggestions that may help.
- Adjust your expectations. For example, if you have a list of 10 things you want to accomplish today, pare it down to two and leave the rest for other days. A sense of accomplishment goes a long way to reducing stress.
- Help others understand and support you. Family and friends can be helpful if they can “put themselves in your shoes” and understand what fatigue means to you. Cancer groups can be a source of support as well. Other people with cancer understand what you are going through.
- Relaxation techniques such as audiotapes that teach deep breathing or visualization can help reduce stress.
- Activities that divert your attention away from fatigue can also be helpful. For example, activities such as knitting, reading or listening to music require little physical energy but require attention.
- If your stress seems out of control, talk to a healthcare professional. They are here to help.
When Should I Call My Doctor?
Although cancer-related fatigue is a common, and often expected, side effect of cancer and its treatments, you should feel free to mention your concerns to your healthcare providers. There are times when fatigue may be a clue to an underlying medical problem. Other times, there may be medical interventions to help control fatigue.
Finally, there may be suggestions that are more specific to your situation that would help in combating your fatigue. Be sure to let your doctor or nurse know if you have:
- Increased shortness of breath with minimal exertion.
- Uncontrolled pain.
- Inability to control side effects from treatments (such as nausea, vomiting, diarrhea, or loss of appetite).
- Uncontrollable anxiety or nervousness.
- Ongoing depression.