Last Modified: January 17, 2012
Many survivors who have previously received or are currently undergoing chemotherapy report experiencing cognitive changes, often referred to as "chemo-brain." These changes include difficulty with short term memory, multi-tasking, new learning, reading comprehension, working with numbers and a decrease in concentration ability. For many years, this was attributed by physicians and researchers to depression or anxiety over the diagnosis and treatment of cancer. More recently, researchers have begun to study and document what survivors have been saying all along; cognitive changes after chemotherapy are real. Although we are not yet able to pinpoint whether only certain chemotherapy drugs are responsible, it seems certain that the effects are cumulative. That is, those who receive more chemotherapy tend to experience greater deficits. Studies have found that cognitive ability can improve over time in some survivors, but deficits are still present in many long-term survivors, even years after treatment. Each person's experience is unique, making it difficult to predict what deficits, if any, a person will experience, and whether or not they will persist after treatment.
In recent years, a number of studies have been reported, many showing some level of decline in brain function in cancer survivors post therapy, although some studies have not found any change. The effect can be a worsening of a pre-existing cognitive issue, or a new change in function. Some study participants worsen during therapy and gradually improve after, while others find their impairments are long-lasting, if not permanent.
What are these cognitive effects exactly? Survivors identify changes in attention / concentration, processing speed, verbal and visual memory, multitasking, word finding, and difficulty with organization. These effects can lead to an inability to perform one's job, difficulty managing family/home responsibilities and even social withdrawal for fear of embarrassment. Family, friends and co-workers often expect the survivor to be "back to normal", only adding to the stress of cognitive changes.
So, what can a person do to improve their brain function? Unfortunately, the research in this area is in its infancy and it will likely be a number of years before we have any definitive answers to that question. We can take some lessons from research in dementia and Alzhiemer's Disease and throw in a dash of common sense to develop some tips to regaining and/or optimizing your brainpower.
Some medications are being studied as potential treatments for cognitive changes, but there is not yet enough data to support their use. Methylphenidate (Ritalin) and dexmethylphenidate HCL (Focalin), medications used to treat attention deficit hyperactivity disorder (ADHD) and modafinil (provigil), a medication approved to treat narcolepsy, have been studied in cognitive dysfunction after cancer therapy. The theory is that these medications stimulate the brain and therefore may result in improved concentration, memory and attention, as well as fatigue. Along the same lines, caffeine is an over the counter stimulant that improves cognitive function for millions of people every day. It is a relatively safe way for many people to stimulate their brain function.
Certain herbal therapies may be of some benefit. Ginseng has shown some positive effects on cancer-related fatigue. In the book "Your Brain After Chemo", the authors point out that not all ginseng is created alike. Some companies use a manufacturing process called alcohol extraction, which has been shown to have estrogen-like properties. That is a concern for people with estrogen sensitive tumors. They note that it can be difficult to determine the manufacturing process and if the product is free of contaminants. Ginkgo biloba is often promoted as a memory enhancer, but studies have not found this to be true. One large study of elderly patients found no decrease in Alzheimer's disease, and actually saw an increase in dementia and stroke in the group taking the supplement. Ginkgo biloba increases the risk of bleeding and should be used with caution. As with all herbal therapies, just because they are touted as "natural" does not mean they do not have side effects. Investigate the possible side effects of any supplement, as well as the reputation of the manufacturer and their products. The website consumerlab.com independently tests herbal therapies and vitamins for purity. It charges a fee to join, but this keeps them free from advertising influence and is minimal compared to the 34 billion dollars American consumers spend on alternative medicine every year.
Cognitive rehabilitation programs are structured programs utilizing exercise, tasks that use memory and puzzles to "rehabilitate" one's mind. These programs are typically used for people with brain injuries, but therapists have tailored programs for cancer survivors. A number of companies offer computer programs that aim to improve brain function. There are currently studies ongoing looking at the effectiveness of these programs in cancer survivors, so stay tuned.
Puzzles using numbers, like Sodoku, may help "exercise" your brain. Dan Silverman, MD, PhD, co-author of Your Brain After Chemo, feels these may be beneficial, but it is not known, for example, how well completing a crossword puzzle translates to an effect on verbal memory. It would be helpful if future research looked at these "brain games". It is likely that any brain stimulation may be helpful and certainly cannot hurt, whether through a game, taking a course at a local school or joining a book discussion club.
Fatigue can enhance cognitive problems, so avoiding fatigue by getting enough sleep, incorporating exercise into your life and eating a healthy diet.
It is important to remember that some very treatable problems can result in cognitive difficulties, such as thyroid dysfunction, depression and anxiety, so it is important to exclude or treat these diagnoses. Hypothyroidism (low thyroid hormone levels) is a common issue for survivors and can make you feel "fuzzy" or "out of it." This is easily treatable with supplemental thyroid hormone. Survivors who may be depressed or experiencing anxiety would benefit from consulting with a psychiatrist or psychologist experienced in working with cancer patients or survivors. Don't just assume your cognitive concerns are due to chemo-brain.
As you can see, there is no "quick fix" for chemo-brain, so get creative and incorporate things into your daily life that can help combat the symptoms.
Most importantly, know your limitations. Don't take on tasks that require too much multi-tasking. Ask for help. Try to keep a positive outlook and find some humor in your "chemo-brain moments".
Jansen CE et al. (2008). Preliminary results of a longitudinal study of changes in cognitive function in breast cancer patients undergoing chemotherapy with doxorubicin and cyclophosphamide. Psycho-Oncology. 17(12):1189-95, 2008.
Mitsiades N et al. (2008). Cognitive effects of hormonal therapy in older adults. Seminars in Oncology. 35(6):569-81, 2008.
Nelson CJ (2007). Chemotherapy and cognitive deficits: mechanisms, findings, and potential interventions. Palliative & Supportive Care. 5(3):273-80, 2007.
Silverman D & Davidson, I (2009). Your Brain After Chemo. Cambridge, MA: DaCapo Press.
Weiss, B (2008) Chemobrain: a translational challenge for neurotoxicology. Neurotoxicology. 29(5):891-8, 2008.
The American Cancer Society: Chemo Brain
CANCERcare Information sheets on Chemo-Brain (under Managing side effects)