Cognitive Changes: Detailed Information

Cognitive changes are problems with thinking, including memory, concentration and behavior. These changes can influence many parts of your life, such as your ability to work or even to complete everyday tasks. Some cancers, cancer treatments and medications can cause cognitive changes for cancer survivors. However, there are many other causes of cognitive changes that are not related to cancer.

Experiencing problems with thinking and concentration can be very scary. It can be very upsetting to realize that you have successfully treated your cancer but are now experiencing cognitive problems as a result of the cancer, its treatment or some other cause. Just because you had chemotherapy, radiation or surgery does not mean that you will definitely have cognitive changes. But it is important to know what the symptoms are so that you know what to look for.

If you do notice problems with thinking, memory or behavior, talk to your health care team right away. To get the correct treatment, it is important to find out what is causing the cognitive problems.

Sometimes the cognitive changes that are related to cancer are very minor and are reversible, meaning the changes will go away. Some cognitive changes can be more noticeable, however, and may not be reversible. Cognitive changes can happen suddenly (acute onset), or they can come up slowly over time (gradual onset).

Who is at risk for cognitive changes?

Survivors who experienced the following might be more at risk for cognitive changes:

• Central nervous system (CNS) involvement with tumor
• Treatments administered directly to the CNS
• Treatments administered when extremely ill
• Chemotherapy and radiation given to the brain at the same time
• Chemotherapy given into the spinal fluid after radiation

Cancer survivors who did not experience any of the above procedures may still experience some cognitive changes. Cognitive changes can occur in survivors of all ages who received all types of chemotherapy and radiation. Those who had surgery to remove a brain tumor can also experience cognitive changes. The frequency and severity of cognitive changes associated with chemotherapy varies with the dose and type of medicine used. Cognitive changes are sometimes related to higher dose treatment of chemotherapy and the use of immunotherapy, treatment to boost the immune system. The frequency and severity of cognitive changes associated with radiation and surgery to remove a brain tumor depends on the amount of damage caused to surrounding healthy tissue.

What are some of the symptoms of cognitive changes?

Acute onset cognitive changes (delirium)
Acute onset cognitive changes are those that occur suddenly and come and go with no real pattern, often during treatment with chemotherapy agents. Delirium is the term used to describe these cognitive changes. Certain medications and chemotherapy treatments can cause delirium, and it may be reversible.

Gradual onset cognitive changes (dementia)
Gradual onset cognitive changes are considered to be chronic, meaning they come about slowly over time and are long-lasting. Dementia is the term used to describe these cognitive changes. Symptoms of dementia might not appear until you finish active treatment for cancer. Dementia symptoms can be very mild and only slightly noticeable, or they can be very noticeable.

Sometimes survivors experience slight changes in their ability to remember or concentrate well after they have received chemotherapy. This very mild form of dementia is sometimes called “chemo-brain.”

What causes cognitive changes in cancer survivors?

Cancer cells in the brain (a tumor) destroy healthy cells and can cause cognitive changes. Chemotherapy, radiation and surgery are used to remove or destroy cancer cells, but these treatments can also damage the surrounding healthy cells. Depending on how much damage occurs, there could be noticeable problems with thinking, memory and behavior. Additionally, chemotherapy can cause factors like fatigue and anemia, which may also lead to cognitive problems, particularly with being able to pay attention.

Also, a survivor can experience other conditions that may or may not be related to cancer or its treatment that can cause cognitive changes. Some of these conditions are reversible; some are not.

Some other conditions that can cause cognitive changes:

• Medication problems
• Stress
• Anxiety
• Depression
• Electrolyte derangements
• Hypoxemia (low oxygen levels)
• Other diseases of the brain (Alzheimer’s disease and Parkinson’s disease for example)
• Thyroid problems
• Severe nutrition problems

It is important to discuss with your health care team all of the possible causes of cognitive problems so that you receive the correct diagnosis and treatment.

When do cognitive changes occur?

Cognitive changes can occur at any point during your experience with cancer. Sometimes cognitive changes are the first sign of a brain tumor. Cognitive changes may also occur after completing cancer treatment or after taking certain medications.

Delirium may occur suddenly during treatment. Delirium usually occurs after an identified cause (chemotherapy, for example) and is often reversible.

Dementia occurs gradually over time and usually occurs after treatment is completed. Dementia may be harder to identify than delirium, and may not have one identifiable cause. It can develop as early as three months after radiotherapy, but can also occur 48 months or longer after completion of radiation therapy to the brain. “Chemo brain” can occur during chemotherapy treatment or after the treatment has been completed. Dementia symptoms may also occur after surgery to remove a brain tumor.

Can cognitive changes be cured?

Whether cognitive changes will improve or be permanent depends on their cause. Acute cognitive changes (delirium) that occur because of certain medicines often improve when you stop taking the medicine. Chronic changes (dementia) are often not reversible, but may be improved if the cause of the problems can be corrected.

If you notice changes in your thinking, memory or behavior, keep a record of the problems that you have and ask your family or friends to watch for additional problems. Make an appointment to talk to your health care team about these symptoms as soon as possible. Treating the underlying condition often reduces or removes cognitive problems.

What are some suggestions for survivors who may be experiencing cognitive changes?

• Use the Cancer Survivor’s Health Journal to communicate symptoms and side effects of medicine with your health care team.
• Take the medication your health care team prescribes to help cognitive changes as directed.
• Avoid dangerous activities if you are alone.
• Ask your family to watch for safety issues.
• Talk to your family and an attorney about legal documents you may need to make sure your medical and financial wishes are respected.
• Get plenty of sleep.

This document was produced in collaboration with:
Terri S. Armstrong, MS, APRN, BC
Advanced Practice Nurse, Department of Neuro-Oncology
M.D. Anderson Cancer Center
Clinical Assistant Professor and Doctoral Student
University of Texas-Houston School of Nursing

Cognitive Changes: Suggestions

Use the Cancer Survivor’s Health Journal to communicate symptoms and side effects of medicine with your health care team:

• The Cancer Survivor’s Health Journal can be found in the Survivorship Tools area.
• Use the Health Diary to record any cognitive changes that you notice. Keeping a Health Diary will help you to remember examples when you had difficulty concentrating or remembering simple things. These examples can be valuable for communicating with your health care team.
• Use the Health Care Team Appointment document to write down everything you want to ask your health care team. You can write notes and questions on the sheet between appointments.
• Use the List of Medications to keep track of your medications. Bring this document to the appointment along with all of your medication bottles. This lets the team know all the medications you are taking, including vitamins and over-the-counter medications.
• Use the Health Care Team Appointment document to take notes during the appointment and to write down your next appointment date.
• Keep all of these documents together in a binder and bring it with you to your appointments.
• Bring extra copies of all of these documents with you to give to the health care team. You can also fax or mail these documents in before the appointment. Having the health care team read your documents may be an easier way for you to communicate.
• You can store pamphlets, medication side effect inserts and important phone numbers in your binder so that everything is in one place.
• You can also contact your health care team by phone to let them know of your concerns. This will alert your team about the changes you are experiencing and help make sure that you talk about them at your next appointment.

Take the medication your health care team prescribes to help cognitive changes as directed:

The very nature of cognitive changes and memory challenges may make it difficult to remember to take prescribed medication. There are strategies that can help you to remember.

Some strategies for taking medication appropriately:

• Take the medication at the same time every day
• Use a medication reminder or pill dispenser
• Talk to your health care team before you stop taking any medication
• Keep a journal of medications you are taking noting any side effects of the medications

Check with your health care team before using any over the counter or prescription medications, or natural products to treat your symptoms.

Avoid dangerous activities if you are alone:

If you are having severe problems with concentration and memory, you may find yourself distracted and potentially placing yourself in harm’s way during certain activities.

Examples of activities you may want to avoid when alone:

• Cooking
• Using tools with which you can injure yourself
• Traveling to unfamiliar places

Ask your family to watch for safety issues:

If you have trouble with memory or concentration, you may want to sit down with your family and share your concerns. Discussing ways they can assist you in going about your daily activities may put your mind at ease in your daily activities.

Examples of ways your family can help:

• Create a checklist to keep by the door to review if you have turned off kitchen appliances
• Have someone drive you to appointments if traffic is too distracting

Talk to your family and an attorney about legal documents you may need:

• When you are experiencing cognitive problems, it is important to make sure your medical and financial wishes are respected. Talk to your family about your wishes and talk to an attorney about the legal documents that you will need.
• You can use the Practical Information Summary to organize information on your family, medical wishes, finances and estate planning. The Practical Information Summary can be found in the Survivorship Tools area.

Get plenty of sleep:

Rest may not get rid of the problem but may help make it better.

• Limit napping during the day
• Develop an exercise plan with your health care team
• Have a bedtime ritual, such as meditating
• Use aromatherapy, reading or other relaxing activities to prepare for sleep