Chemofog: Cancer-related Cognitive Impairments In 5 Questions

Everyone knows that chemotherapy causes nausea and fatigue. But have you heard of chemofog? This strange word from English refers to the cognitive impairments related to cancer treatments. We will explain what it is and how to cope with it in 5 questions.

1- What is chemofog?

The term chemofog is a portmanteau composed of two English terms: chemo for chemotherapy and fog for mist.

The London fog is mentioned to describe the thick mist that regularly settles over the city of London... This vivid word is therefore an excellent way to describe the cognitive impairments that cloud the brain of cancer patients. It is also sometimes referred to as chemobrain (literally: chemo brain).

2- What are the symptoms of chemofog?

According to various studies, **between 40 and 72% of patients treated for cancer** suffer from chemofog. These figures make this problem the second most common complaint among patients, after fatigue but before pain!

It should be noted, however, that only 30% of these patients present a real cognitive impairment. For others, it is more of a feeling, **a sense of mental confusion** that is nonetheless difficult to manage on a daily basis.

This cognitive fog manifests through **various symptoms**, including:
• difficulties in concentrating and memorizing new information.
• inability to perform multiple tasks at the same time.
• difficulties in finding words.
• difficulties in orienting oneself in space.
• inability to remember where one has placed an object or where one has put their keys, for example.

3- What are the causes of chemofog?

For years, doctors and patients alike attributed the symptoms of chemofog to the toxicity of chemotherapy. Although some chemotherapy treatments can cross the blood-brain barrier and directly affect brain function, it is now known that these molecules are not solely responsible for the cognitive impairments in patients.

This problem is multifactorial. This is why some specialists prefer to speak of cancerfog rather than chemofog.

Among the various possible causes of this mental fog, we can particularly note:
• the overall inflammatory state linked to the cancer itself, which could indirectly disrupt the patients' brain capacities.
• all treatments, including hormone therapy in patients with hormone-dependent breast cancer.
• the psychological impact of the disease, with the shock of a cancer diagnosis and the anxiety or even depression that can result from it.
• the lack of sleep caused by all the previous factors.

4- How long does chemofog last?

If you feel like you're losing your mind since starting your cancer treatments, rest assured! For most patients, chemofog is a temporary condition that fades about a year after stopping treatments.

Only elderly patients and those fatigued by treatments may experience this type of cognitive trouble for several years. We are not all equal in facing this problem because it depends on cognitive reserve, which is the stock of neurons unique to each person.

In any case, this mental fog is not inevitable, as it is possible to alleviate its symptoms by training your brain to search for words or orient yourself in space, for example. Some hospitals, such as those in Bordeaux and Caen, offer memory consultations and cognitive rehabilitation workshops.

5- How to deal with chemofog?

At home, a few simple tips can help you manage the effects of chemofog:
• Make lists in a notebook or on your smartphone of important things to remember, such as appointment dates and birthdays.
• Keep a journal to describe your memory and concentration problems so you can better explain them to your doctor.
• Choose a place in the house to put a catch-all basket and store small items that you may lose, especially your keys and wallet.

You can also retrain your concentration with games like word searches or sudoku, but this brain training should remain fun. It should not become an additional burden during your treatments!

More broadly, your lifestyle is very important to cope with the side effects of your treatment. You need to take time to rest and ensure quality sleep to alleviate cognitive disorders. Relaxation techniques such as hypnosis, sophrology, and meditation can also help you clear your mind of worries to have more mental space available.

Don't hesitate to talk about it around you, ideally with a psychiatrist or psychologist! There is no shame in losing some mental sharpness due to your treatment.

Today, chemofog is no longer a taboo but a known and recognized side effect by caregivers. For patients, it is important to address these cognitive disorders to facilitate the return to a normal life, both personally and professionally.