Is it chemo brain or something else?

Chemo brain is common complain among cancer survivors who underwent chemotherapy. It is a condition described as “a mental fog and inability to concentrate that persist long after treatment” and has been assumed to be a side effect of chemotherapy.

A few examples of chemo brain manifestation (source: American Cancer Society, ACS) are given below:

• Forgetting things that they usually have no trouble recalling — memory lapses
• Trouble concentrating — they can’t focus on what they’re doing, may “space out”
• Trouble remembering details like names, dates, and sometimes larger events
• Trouble multi-tasking, like answering the phone while cooking, without losing track of one of them — less ability to do more than one thing at a time
• Taking longer to finish things — disorganized, slower thinking and processing
• Trouble remembering common words — unable to find the right words to finish a sentence

But is it really the chemotherapy that causes this problem dubbed by experts as “mild cognitive impairment?”

Researchers at the University of Miami Miller School of Medicine looked at data collected by the National Health and Nutrition Examination Survey (NHANES) from 2001 to 2006. A total of 9819 adults aged 40 and older were studied. Of these, 1305 had a history of cancer. The subjects were asked the following question:

“Are you limited in any way because of difficulty remembering or because you experience periods of confusion?”

Results of the survey showed:

• 8% of those without cancer history reported some form of memory impairment.
• 14% of those with cancer history reported similar impairment.
• After controlling for confounding factors, the likelihood among the cancer survivors to have memory impairment rose to 40%. Yet, some of these people have not undergone chemotherapy.

The researchers believe that this impairment may be due to a lot of things (and not only chemotherapy), such as:

“chemotherapy, radiation or hormonal therapy, or to something about the disease itself which can change brain chemistry, or to psychological distress.”

In fact, the term “chemo brain” is actually an inaccurate, even misleading term.

According to lead author Dr. Pascal Jean-Pierre, the so-called chemo brain is becoming national problem but can be treated by behavioral interventions and medications (e.g. antidepressants).

The ACS also lists the following factors that can contribute to cognitive impairment of cancer patients:

• The cancer itself
• Other drugs used as part of treatment (such as anti-nausea or pain medicines)
• Patient age
• Stress
• Low blood counts
• Sleep problems
• Infection
• Depression
• Tiredness (fatigue)
• Hormone changes or hormone treatments
• Anxiety or other emotional distress