Many patients experience "chemobrain" — mental clouding or fogginess — during and after cancer treatment.
Fremonta Meyer, MD, a clinical psychiatrist in Dana-Farber's Department of Psychosocial Oncology and Palliative Care, discusses tips for managing chemobrain.
What is chemobrain?
Chemobrain refers to the cognitive impairment that can occur after cancer treatment. It's not limited to people who get chemo (surgery and radiation can also contribute), but it's more noticeable if you had chemotherapy.
What are some of the most common symptoms of chemobrain?
Symptoms may include decreased short-term memory, problems finding words, short attention span, and difficulty concentrating and multitasking.
The best way to get a complete picture of your cognitive functioning is to have neuropsychological testing. Your oncologist can refer you for this evaluation. Information from neuropsychological testing can also be extremely helpful to share with your employer or school if you are hoping to get accommodations at work or extra time for exams, homework etc.
Is chemobrain all based on body and mind fatigue?
Chemobrain is partially based on body and mind fatigue. Animal studies have shown that chemotherapy may cause temporary reductions in cell growth in brain areas (such as the hippocampus) that control learning and memory.
Do all patients experience chemobrain, or are some patients more likely to get it?
A majority of people report cognitive problems during chemo (67% in one study). Women may be more at risk than men. Genetic differences (small variations in DNA sequences in genes, called polymorphisms) may also increase risk. These occur in a variety of genes, not just cancer-causing genes.
Does chemobrain ever go away?
For most patients, chemobrain improves within 9-12 months after completing chemotherapy, but many people still have symptoms at the six-month mark. A smaller fraction of people (approximately 10-20%) may have long-term effects.
For the minority of people who do have long-term effects, they can be noticeable even 10 years after completing treatment. However, these side effects should be stable and not worsening. If they are getting worse 10 or more years later, you should speak with your doctor.
What can I do to reduce symptoms of chemobrain?
Regular exercise is helpful for alleviating chemobrain symptoms. Aerobic exercises – walking, running, dancing, or cycling, to name a few – are probably better, but one study did show that resistance and strength training helped as well.
It's also important to make sure you're receiving treatment for any depression, anxiety, or sleep problems (including sleep apnea). Make sure you also have had your thyroid, vitamin D and B12 levels checked.
Cognitive treatments including brain games through websites such as lumosity.com and positscience.com, and EEG biofeedback (another form of "brain exercise" that naturally trains your brain waves to be in a less turbulent state), are significantly more effective than medications for treating chemobrain.
Are there specific memory games to use to remember what you just forgot?
It's actually best to handle the information differently to increase the chance you will remember it. Try to link a visual image with the information you hope to remember. If it's a name, think of something silly that rhymes with it. If you can, (don't be embarrassed to say you need to do this) write it down.
Are certain chemotherapy drugs more likely to cause chemobrain? Is there a relationship between the dosage and/or duration of chemotherapy, and the severity or duration of chemobrain?
Cyclophosphamide, Adriamycin, 5-FU, and taxol seem to be particular culprits of chemobrain, but there are others that can cause the condition. "Dose dense" chemotherapy may be associated with more chemobrain symptoms, but chemotherapy can cause symptoms regardless of whether that specific drug crosses the blood-brain barrier.
Do any other cancer medications, such as hormone therapy like tamoxifen, cause or prolong chemobrain?
One study suggested that people who receive both chemotherapy and tamoxifen may have more prolonged cognitive symptoms than those who receive only chemotherapy.
Tamoxifen and aromatase inhibitors may have a subtle negative effect on cognition, especially verbal memory and word finding. Tamoxifen is probably more likely to cause problems than aromatase inhibitors. Among aromatase inhibitors, exemestane has androgenic properties that may be less likely to cause cognitive problems.
How can you differentiate chemobrain from other mental problems such as Alzheimer's disease, dementia, or simple forgetfulness?
In Alzheimer's, memory doesn't respond to cues whereas in chemobrain, cues are helpful. For example, if I asked you to remember "yellow" and asked what it was a few minutes later, a clue such as "it was a color" would be helpful for chemobrain, but not for people with Alzheimer's.
Other types of dementia usually involve personality changes, motor changes (stiffness, tremors, falls) or hallucinations, which are not typical of chemobrain. However, it can be hard to differentiate chemobrain from age-related forgetfulness when symptoms are mild.
How can I be sure my forgetfulness is caused by chemobrain, not my cancer metastasizing to the brain?
It's not possible to know for certain without a scan (MRI) of the brain. If you have any other neurological symptoms such as headaches, new balance problems, or weakness/numbness in a body part, it is very important to ask your oncologist about an MRI.
Does having chemobrain increase my risk of getting Alzheimer's or dementia?
No – in one large study, breast cancer survivors who received chemotherapy actually had a lower risk of Alzheimer's and other dementias compared to those who did not receive chemotherapy.
How do I know if I am experiencing is chemobrain and not depression?
Depression can also have cognitive symptoms, such as problems with concentration, short-term memory, and multitasking. However, in depression, people also feel sad, irritable, and lose enjoyment and motivation to pursue valued activities. These symptoms are not often seen in chemobrain.
Can stem cell transplants cause chemobrain-like symptoms?
Cognitive problems after a stem cell transplant are very common and can be caused by a number of factors, including steroids and tacrolimus, as well as pain and anxiety medications. Because patients are immunosuppressed, we do also consider infections, which occur at times. If you are noticing worsening cognitive symptoms, it is important to speak with your doctor.
I seem to be better able to remember things as time passes. Is this possible or have I learned to compensate?
It could be natural improvement, which can continue gradually in the first 1-3 years after chemotherapy, or it could be related to improved sleep, anxiety, and mood – all of which can impair cognition. Or you may have developed compensatory strategies.
Is there anything I shouldn't do when I'm experiencing chemobrain, such as drive?
Not all, but some, people with chemobrain report problems with parking accurately and with driving, especially on less familiar routes. If you do drive, be cautious, stick to routes you know, and bring a companion if possible.
Do you ever recommend treatment with psychotropics for chemobrain? If so, what type?
Some people benefit from taking stimulants such as methylphenidate (Ritalin), dextroamphetamine (Adderall), or modafinil/armodafinil (Provigil/Nuvigil). These tend to be most helpful for fatigue and improving attention and concentration.
Have brain stimulation techniques been used successfully for chemobrain?
This is an area that deserves more research. There are some studies that suggest that EEG biofeedback is helpful. However, there is no research testing whether transcranial magnetic stimulation (noninvasive) or deep brain stimulation (surgical/invasive) may be useful for chemobrain. But these treatments are effective for some people with depression and may improve cognitive symptoms associated with depression in those people.
How can I help others understand the cognitive issues chemobrain causes?
Sometimes it's helpful to use an analogy, such as losing a reliable backhand in tennis: You can try to compensate by using your forehand only, and you may manage some of the time by doing that, but it takes much more effort and affects your performance.
What type of research has been done on chemobrain?
There have been studies measuring people's subjective complaints and objective neuropsychological testing before and after chemotherapy. Brain imaging studies have been done to measure blood flow and water diffusion in the brain before and after chemotherapy. Recently, there have been more treatment studies to see if brain games and neuro-feedback might help chemobrain.
What is cognitive rehabilitation and where can I get this help?
Cognitive rehabilitation is a treatment that gives you strategies to manage your cognitive impairment. It is generally covered under your health insurance's occupational therapy benefit. In Boston, it is available at Mass General Hospital, Spaulding Rehabilitation Hospital, and from private practitioners. You will need a referral from a physician, so speak with your doctor if this is something that you are interested in.