Fatigue, nausea and hair loss are some of the side effects typically associated with chemotherapy.
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But over the last few decades, researchers and cancer doctors have increasingly understood that many cancer patients also experience significant and frustrating cognitive, or mental, side effects from cancer treatment.
Chemo brain, more formally referred to as chemotherapy-induced cognitive impairment, is a mental fog that can affect cancer survivors’ memory, attention and ability to process information. And it’s quite common.
One review of studies found that up to 75% of cancer patients experienced cognitive side effects during treatment, and in 35% patients, those effects continued after treatment ended. A smaller percentage of patients reported some cognitive effects even before treatment began.
“One of the challenging things about chemo brain is that, while we all recognize that it’s a real phenomenon, it hasn’t been studied as robustly as other parts of patient care,” says breast cancer oncologist Megan Kruse, MD.
But researchers are actively working on learning more about who’s most at risk and what treatment strategies might help.
What is chemo brain?
Some cancer patients report having trouble with:
- Remembering things.
- Finding the right words.
- Processing information.
- Taking longer to complete tasks.
While most people start to notice these effects while they’re going through cancer treatment, others don’t experience them until afterward, Dr. Kruse says.
“It may be that someone feels like they’re coping pretty well during treatment, and it’s not until their life returns to normal, where they’re back in their usual environment of work or family care, that they notice these changes,” she explains.
Unfortunately, it’s not exactly clear why many people experience chemo brain. Some studies have suggest that chemotherapy has toxic effects on the brain that mimic the effects of aging. But that doesn’t explain why some people experience cognitive difficulties before chemotherapy, or why patients who receive other forms of treatment, such as radiation or hormonal changes, also report them.
Dr. Kruse notes that the stress of a cancer diagnosis and treatment can also be a factor. Stress can lead to difficulty sleeping, changes in diet and activity levels, anxiety or depression that may also cause or worsen these problems.
“All those things seem to play a role in cognitive function and memory,” she says.
Some studies have also suggested that the cancer itself, or the presence of inflammation or certain genes, could affect someone’s risk for experiencing cognitive difficulties during treatment.
Coping with chemo brain: an individual approach
For most people, the mental fogginess that comes with cancer treatment gets better with time. But Dr. Kruse underscores the importance that patients talk with their primary care doctor and oncologist if they notice these changes.
“Patients are not always inclined to talk about this, because it feels like it’s not a concern that we can help with, or maybe one that we don’t want to hear about, but that’s far from the truth,” Dr. Kruse explains.
“Patients go through their treatment in order to live their lives the way they want to live them, and this certainly can have a huge impact on quality of life and relationships, so we do want to address it.”
Their recommendations will depend on what a patient is struggling with and how much their life is impacted.
“We recommend that patients keep a journal of situations where they’re noticing these changes, or when a family member brings it up,” Dr. Kruse advises. “That way we can hone down on what interventions might be best for them.”
If the issues are related to recall and short-term memory, small adaptations to daily life may help, such as:
- Keeping lists of reminders.
- Carrying a notepad and pen (or using a notetaking app).
- Using a calendar to track important days and events.
- Labeling cabinets or drawers in the house where important items are stored.
- Regularly performing light physical activity, which studies show can benefit the brain.
For more complex cognitive processing issues, patients may benefit from working with a neuropsychologist, occupational therapist or a speech language pathologist. Certain medications may also help with memory issues after chemotherapy.
“We also always offer patients a referral to a psychologist or psychiatrist,” Dr. Kruse says. They can help patients cope with stress, as well as address any underlying conditions like anxiety, depression or sleep problems that can also cause cognitive symptoms.
Finally, Dr. Kruse underscores the importance of enlisting family, friends and other members of a cancer survivor’s support network in navigating life after cancer, including coping with the lasting physical and cognitive side effects of treatment.
“Certain tasks in the house might need to be redistributed, or a patient might need their workload adjusted to match whatever their best skill set is now,” Dr. Kruse says. “For cancer survivors, the support aspect is really key.”