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For many years cancer survivors have worried about, joked
about, and been frustrated with the mental cloudiness they notice
before, during, and after chemotherapy. We don't know its exact cause,
but this mental fog is commonly called chemo brain.
Patients have noticed chemo brain for some time, but only recently have
studies been done that could start to explain it.
Research has shown that some cancer drugs can, indeed, cause
changes in the brain. Imaging tests have shown that in some patients,
the parts of the brain that deal with memory, planning, putting
thoughts into action, monitoring thought processes and behavior, and
inhibition are smaller after chemotherapy.
Some people report having these symptoms even before they
start treatment. Others report it even though they have not had
chemotherapy. Still others notice the problem when they are getting
hormonal treatments. So the term chemo brain may not be completely
accurate, but it is what most people call it right now.
Though the brain usually recovers over time, the sometimes
vague yet distressing mental changes cancer patients notice are real,
not imagined. These changes can make people unable to go back to their
school, work, or social activities, or make it so that it takes a lot
of mental effort to do so. They affect daily activities and need to be
researched further.
What is chemo brain?
Here are just a few examples of what patients call chemo
brain:
- forgetting things that they usually have no trouble
recalling—memory lapses
- trouble concentrating—they can't focus on what
they're doing
- trouble remembering details like names, dates, and
sometimes larger events
- trouble multi-tasking, like answering the phone while
cooking, without losing track of one of them—less ability to
do more than one thing at a time
- taking longer to finish things—slower thinking
and processing
- trouble remembering common words—can't finish a
sentence because you can't find the right words
For some people these effects happen quickly and only last a
short time, while others have mild, long-term mental changes. Usually
the changes that patients notice are very subtle, and others around
them may not even notice any changes at all. Still, the people who have
problems are well aware of the differences in their thinking. Many
people do not tell their health care team about this problem until it
affects their everyday life.
Doctors and researchers call chemo brain "mild cognitive
impairment" and define it as being unable to remember certain things
and having trouble finishing certain tasks or learning new skills.
Is chemo brain real?
Yes, chemo brain is real, but its cause is unknown. How often
it happens, what may trigger it, or what can be done to prevent it, is
also unknown.
Pictures of the brain have shown changes in the brain activity
of breast cancer survivors treated with chemo when compared with those
who were not treated with chemo. These changes were still seen on scans
5 to 10 years after treatment stopped. Chemo brain could be caused by
any one or any combination of the following factors:
- the cancer itself
- chemo drugs
- other drugs used as part of treatment (such as anti-nausea
or pain medicines)
- patient age
- stress
- low blood counts
- sleep problems
- infection
- depression
- tiredness (fatigue)
- hormone changes
- anxiety
What is known is that chemo brain is a real problem that
affects both men and women. Even though chemo does not seem to be the
only cause, studies have suggested that up to 70% of people who get
chemo will notice symptoms of chemo brain.
What can I do to manage chemo brain?
Day-to-day coping
Experts have been studying memory for a long time. Many
resources are available to help you sharpen your mental abilities and
manage the problems that may come with chemo brain. Some things you can
do are:
- Use a detailed daily planner. Keeping everything in one
place makes it easier to find the reminders you may need. Serious
planner users keep track of their appointments and schedules, to do
lists, important dates, phone numbers and addresses, meeting notes, and
even movies they'd like to see or books they'd like to read.
- Exercise your brain. Take a class, do word puzzles, or
learn to do something new.
- Get enough rest and sleep.
- Exercise your body. Regular physical activity is not only
good for your body, but also improves your mood, makes you feel more
alert, and decreases tiredness (fatigue).
- Eat your veggies. Studies have shown that eating more
vegetables can help you maintain brain power.
- Set up and follow routines. Pick a certain place for
commonly lost objects and put them there each time. Try to keep the
same daily schedule.
- Don't try to multi-task. Focus on one thing at a time.
- Track your memory problems. Keep a diary of when you notice
problems and the events that are going on at the time. (You might track
this in your planner.) Medicines taken, time of day, and the situation
you are in may help you figure out what affects your memory. Keeping
track of when the problems are most noticeable can also help you
prepare by not planning important conversations or appointments during
those times.
- Try not to focus on how much these symptoms are bothering
you. Accepting the problem will help you deal with it. As many patients
have noted, being able to laugh about things you can't control can help
you cope. And remember, you probably notice your problems much more
than others do. Sometimes we all have to laugh about forgetting to take
the grocery list with us to the store.
Telling others
Another thing you can do to better manage chemo brain is tell
family, friends, and your health care team about it. Let them know what
you are going through. You may feel relieved once you tell people about
the problems you sometimes have with your memory or thinking.
You are not stupid or crazy; you just have a side effect that
you have to learn to manage. Even though this is not a change that is
easy to see, like hair loss or skin changes, your family and friends
may have noticed some things and may even have some helpful
suggestions. For example, your partner may notice that when you are
rushed, you have more trouble finding things. Tell your loved ones what
they can do to help. Their support and understanding can help you relax
and make it easier for you to focus and process information.
Many large hospitals and cancer centers have specialists who
test brain function, including the symptoms of chemo brain. Testing can
help specialists find the extent of your symptoms and then suggest the
best mental exercises for you. You may want to ask for a referral to
one of these specialists who can help you learn the scope of your
problem and work with you on ways to manage your memory or thinking
problems.
Can chemo brain be prevented?
The cause of chemo brain is unknown and at this time there is
no way to prevent it. It seems to happen more commonly with high doses
of chemo. But because chemo brain is usually mild and most often goes
away over time, proven and effective chemotherapy plans should not be
changed to try to prevent this side effect.
What is being done about chemo brain?
Now that chemo brain has been linked to cancer and its
treatment, studies are being done to learn more about it. Some studies
are looking to find out which chemo drugs and other treatments are more
closely linked to chemo brain. Researchers are also looking at possible
ways to prevent chemo brain, as well as ways to help survivors who are
still having trouble thinking. Researchers are studying other aspects
of cancer treatment that may lead to long-term mental changes, too. For
example, they are looking at the types and doses of chemo the patients
had, other cancer-related symptoms (like tiredness), and genetic
differences among individuals to see if these factors are linked to a
higher risk of chemo brain.
Future directions
Looking at how chemo brain happens
Recent studies have shown clear evidence of nerve damage from
at least some forms of chemotherapy. But studies of the effects of
chemo drugs on brain cells are still rare. This area is a focus of
ongoing research. Scientists must find out which nerve cells or brain
cells are at risk during cancer treatment in order to develop ways to
reduce damage, save brain function, and maintain the quality of life in
long-term survivors.
So far, early studies in the lab and in animals suggest that
certain chemo drugs may harm some nerve cells even after the drug is
stopped. But more research is needed to see if this happens in humans,
too.
There is more concern about chemo brain now because cancer
treatment study results have shown better outcomes with the use of more
aggressive, high-dose drug schedules. There are also newer targeted
drugs that are known to affect certain pathways that are part of nerve
cell formation and stem cell function, which heightens the concern.
Discovering which nerve cells are affected may also let scientists test
new drugs for this side effect when they are being developed.
Preventing chemo brain
Cancer experts also are looking into treatment options that
may protect the brain from chemo side effects. Research is being done
on targeted drugs that focus on the cancer cells and spare normal,
healthy cells, such as brain and nerve cells.
Treating chemo brain
Researchers are also looking at medicines that are now used
for problems like depression, attention-deficit hyperactivity disorder
(ADHD), Alzheimer disease, and dementia as possible treatments for
chemo brain.
Looking for other links to chemo brain
Genetic differences that may make some people more likely to
have symptoms of chemo brain are being explored, too. One particular
gene, called APOE, is being looked at closely. Research has shown that
a version of this gene, called E4, is linked to Alzheimer disease. When
E4 is present, there is an increased chance of thinking problems after
traumatic brain injury, too. Studies are being done to find out if
people who have the E4 gene who get chemotherapy have a higher risk of
developing long-term chemo brain.
Recognizing chemo brain as a treatment side effect was the
first step. Doctors and researchers are now trying to measure it -- how
exactly does it affect patients' brains and cause changes? This
information will hopefully help them find ways to not only treat chemo
brain, but prevent it.
Additional resources
More information from your American Cancer
Society
We have selected some related information that may also be
helpful to you. These materials may be ordered from our toll-free
number.
National organizations and Web sites*
Along with the American Cancer Society, other sources of
information and support include:
American
Psychological Association (APA)
Toll-free number: 1-800-374-2721
Web site: www.apa.org
Provides a hotline to get literature and discuss psychological
concerns. Also makes referrals to state psychological associations to
find a psychologist (sometimes called a counselor or therapist) in a
specific area.
American
Psychosocial Oncology Society (APOS)
Toll-free number: 1-866-276-7443
Web site: www.apos-society.org
Provides referrals for local counseling, therapist, and social support
services, aiming to connect patients and/or caregivers to
psychiatrists, psychologists, nurses, and social workers skilled in the
management of cancer-related distress. All requests are confidential.
CancerCare
Toll-free number: 1-800-813-4673
Web site: www.cancercare.org
Provides free professional support services to anyone affected by
cancer: people with cancer, their loved ones, and caregivers, including
telephone counseling, online support groups, free educational
materials, and telephone workshops
*Inclusion on
this list does not imply endorsement by the American Cancer Society.
No matter who you are, we can help. Contact us anytime, day or
night, for information and support. Call us at 1-800-227-2345 or
visit www.cancer.org.
References
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Dietrich J, Monje M, Wefel J, Meyers C. Clinical Patterns and
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Mayo Clinic staff. Chemobrain. Accessed at:
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Silverman DH, Dy CJ, Castellon SA, et al. Altered
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Last Medical Review: 06/19/2009
Last Revised: 06/19/2009
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