People with cancer who undergo chemotherapy typically expect they will experience some physical reactions, such as nausea, fatigue, and dry mouth, but the symptoms of chemobrain can be not only a real surprise, but a disturbing one as well unless they are prepared for it. If you know how to recognize symptoms of chemobrain, and what you can do to combat them, then the experiences in your life associated with chemotherapy can be managed with less stress and uncertainty.
What is chemobrain?
Chemobrain is a term used to describe the mental symptoms and brain changes that occur in cancer patients when they take chemotherapy drugs. The mental changes may last for only a short time, but for some people they last for years and have a significant impact on their daily lives.
Not all experts agree on the definition of chemobrain. Some say it is mild cognitive impairment, defined by a temporary inability to remember certain things, difficulty learning new skills, or trouble finishing tasks. Others say the term applies only to these features that don’t get better over time. Fortunately, chemobrain symptoms usually happen quickly and go away soon as well.
Because experts do not agree on how to define chemobrain, it is difficult to state how many cancer patients experience it. Estimates range from 15% to 70% of chemotherapy patients who will have brain symptoms. These figures may not take into account people who have cognitive problems associated with their cancer, radiation treatment (which can also cause memory and thinking problems), or other causes.
Symptoms of chemobrain
- Memory lapses: forgetting things you usually have no trouble remembering
- Difficulty concentrating: cannot focus on what you’re doing, spacing out
- Difficulty remembering details: names, dates, and individual events
- Trouble multi-tasking: doing more than one thing at a time becomes difficult, such as talking on your cell phone and walking down the street
- Problems with words: unable to find the right words to finish sentences
What causes chemobrain?
Chemobrain may have more than one cause, especially if the symptoms are short-term. Memory and thinking problems may have been present before chemotherapy started, or the challenges may be associated with other types of treatment, such as hormone therapy or radiation. Brain problems could be caused or exacerbated by any of the following factors:
- The cancer itself
- Use of other medications, such as anti-nausea or pain drugs
- Sleep disturbances
- Hormone changes
- Depression or anxiety
- Low blood counts
- Presence of other health problems, such as heart disease or diabetes
- Nutritional deficiencies
Studies of chemobrain
Animal and human studies of the effects of chemotherapy have shown that the brain is definitely affected. A 2011 study of patients who underwent high-dose chemotherapy and immune-suppression drug therapy before having a stem cell transplant serves as one example. The researchers found that a comparison of early test results with those five years after the transplant reveals that although thinking problems had improved after one year, more than 40% of the patients still experienced mild brain problems after 5 years, including hand speed, dexterity, and word recall.
In another 2011 study, but this one in animals, scientists evaluated the effects of chemotherapy on cell proliferation, memory, and learning in rats exposed to cyclophosphamide, methotrexate, and 5-fluorouracil combinations. They found that learning and memory were impaired after chemotherapy independent of any effects the drugs had on physical activity, and a decline in cell proliferation in the hippocampus, a memory region in the brain.
How to cope with chemobrain
Some patients who experience memory and thinking changes while getting chemotherapy are able to hide these challenges from their family, friends, coworkers, and doctors, but for others the mental changes are obvious or more problematic. Here are some things you can do to cope with chemobrain.
- Inform your doctors and people closest to you. Sharing the problem with trusted individuals can at least reduce some of the stress associated with symptoms of chemobrain. Family and friends may have noticed changes, and talking about it and gaining their support can make it easier for you to cope.
- Keep a detailed daily planner on your computer, phone, or on paper to help you keep track of dates, meetings, addresses, events, and your “to do” list.
- Keep mentally active by reading, doing word puzzles, or learning something new. An online class can be less stressful than attending a real class. A new study among multiethnic Asian breast cancer patients looked at the impact of chemotherapy on their daily lives. None of the 43 participants were familiar with the term or concept of chemobrain. Most of the participants experienced memory loss, speech problems, and difficulty in decision making after chemotherapy. Their coping strategies included practicing qi gong (similar to tai chi), taking alternative medicine to reduce their fatigue, and playing mahjong to stimulate their mind.
- Participate in regular physical exercise. Maintaining your physical health can improve mood, reduce fatigue, and boost alertness.
- Get enough sleep without the aid of sleeping pills. If sleep is a problem, talk to your doctor about nondrug approaches, such as deep breathing, progressive relaxation, or changing your lifestyle habits (e.g., use of caffeine or alcohol).
- Eat a nutritious diet, especially foods rich in antioxidants. Fruits and vegetables can help maintain brain health.
- Set up and maintain a routine. For example, always put your keys in the same place and go to bed at the same time each night.
- Do not multi-task. You will set yourself up for frustration.
- Learn to ask for help. Enlist family and friends to assist with tasks that may be challenging or that tap your energy.
- Keep a daily log of your memory challenges and episodes of confused thinking and talk to your doctor, especially if your difficulties are affecting your ability to work. You and your doctor may detect a pattern associated with your problems that can be resolved. For example, are your memory problems worse in the morning or at night? Do you have more trouble when you are tired or hungry? Do you feel better after exercising?
For now, there are no known ways to prevent chemobrain, and treatment options are being explored. Chemobrain seems to be more of a problem the higher the doses of chemotherapy, and it is more likely to occur if the brain is treated with radiation. The coping strategies noted can go a long way toward improving quality of life when undergoing chemotherapy.
Read more in our Prostate Cancer Health Center.
Briones TL, Woods J. Chemotherapy-induced cognitive impairment is associated with decreases in cell proliferation and histone modifications. BMC Neurosci 2011 Dec 9: 12:124
Cheung YT et al. Cognitive change in multiethnic Asian breast cancer patients: a focus group study. Ann Oncol 2012 Mar 6
Syrjala KL et al. Prospective neurocognitive function over 5 years after allogeneic hematopoietic cell transplantation for cancer survivors compared with matched controls at 5 years. J Clin Oncol 2011 May 2; 29(17): 2397-2404