Chemo Brain: What You Need to Know

If you or a loved has received treatment for cancer, you've probably heard the term "chemo brain". It's a non-medical expression patients use to describe cognitive difficulties they experience during and after cancer treatment, especially chemotherapy.

Symptoms of Chemo Brain

  • Trouble concentrating
  • Lack of memory
  • Trouble completing tasks
  • Difficulty staying organized

Causes of Chemo Brain

The term chemo brain is a bit of a misnomer. While chemotherapy may definitely play a role, it's still a complicated, and, as of yet, little understood, phenomenon. Here, some theories:

Stress. Some critics attribute the cognitive dysfunction of chemo brain to fatigue and worry, which are often present even before the start of chemotherapy. For example, one study found that women awaiting chemotherapy are more vulnerable to cognitive problems related to worry and fatigue. And, according to an article in the National Cancer Institute (NCI) Bulletin, studies measuring cognitive function before and after chemotherapy found that 20 to 30 percent of patients had lower cognitive performance before chemotherapy than would be expected based on age and education.

Medication. Certain drugs, such as Tamoxifen, used to prevent breast cancer recurrence, and hormonal agents may cause advanced cognitive effects.

Biology. Genetic factors, uncontrolled inflammation, and structural brain abnormalities (identified through imaging studies) may also play a role.

Researchers suspect certain aspects of cancer biology may influence cognitive function. They also acknowledge they probably haven't yet identified all the risk factors for cognitive changes and the development of cancer. Furthermore, few cancer patients are treated only with chemotherapy, suggesting chemo brain is due to more than just chemotherapy.

4 Ways to Manage Chemo Brain

While it's important to understand the underlying causes of cancer-related cognitive impairment, it's also helpful to know how to manage and minimize the effects.

1. Exercise both the body and brain. Physical and mental activities build up cognitive reserves, which you can then tap into when you need to overcome challenges, such as cancer treatment. Exercise also helps you reduce anxiety and get a good night sleep, both critical for optimal cognitive functioning.

2. Set yourself up for success. Use calendars, planners, notes, and memory aids to help you remember appointments, medications, and other important information. Do more challenging tasks when you feel your best. Minimize distractions and take frequent breaks.

3. Keep a journal. Record your symptoms and the time and situation when you experience moments of so-called chemo brain. Identifying patterns may also help you develop coping strategies.

4. Share the data from your journal with your physician. She may see patterns in cognitive slips that you may help better manage.

Rajiv V. Datta, MD, FRCS, FACS, FICS, reviewed this article.



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