Cancer and Foggy Thinking: Is Chemotherapy Really the Cause?

"Chemo brain" is a well-known side effect of cancer treatment, but is chemotherapy to blame?

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Foggy thinking is a well-known side effect of cancer treatment, but is chemotherapy to blame?

Women who receive chemotherapy to treat breast cancer have long reported confusion, disorganization, difficulty concentrating and problems recalling conversations following therapy. And because these symptoms occur so soon after exposure to life-saving but toxic drugs, patients have assumed that so-called chemo brain is a direct result of the potent tumor-fighting drugs they have just received.

But in the latest study investigating the phenomenon, researchers led by Bernadine Cimprich, an associate professor emerita at the University of Michigan School of Nursing, says the changes in cognition actually occur before chemotherapy begins, and may worsen after treatment.

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In a presentation at the annual CTRC-AACR San Antonio Breast Cancer Symposium, Cimprich reports that stress and fatigue related to receiving a cancer diagnosis and anticipating chemotherapy may be responsible for triggering muddled thinking. While previous studies have documented the phenomenon of chemo brain, this is the first to link the symptoms to fatigue and stress before treatment. She and her colleagues studied 28 women who received chemotherapy, 37 who received radiation, and 32 healthy controls without cancer. At the start of the study, all the participants completed verbal working memory tasks while their brains were scanned using functional MRI. They performed the same tasks one month after their chemotherapy or radiation treatment.

Even before any of the treatments began, Cimprich says the cancer patients scored lower on the memory tests than the healthy controls. There was a difference among the cancer patients as well, with those anticipating chemotherapy recording the lowest scores and those facing radiation treatment with slightly higher scores. These patterns continued after cancer treatment, with both chemotherapy and radiation patients showing worsening scores on the cognitive tests.

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“We really don’t know what the independent effects of chemotherapy are,” says Cimprich. “What we are saying is that there are likely other factors that may be related to fatigue and worry, factors that start before any treatment, and are then compounded or enhanced by the effects of chemotherapy.”

For some reason, women waiting for chemotherapy showed the most deficits in cognitive functions, which suggests that anticipating the rigorous rounds of treatment and the potential side effects, including hair loss, nausea and vomiting, causes more psychological distress than concerns about radiation therapy.

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The findings, in some ways, should be reassuring for breast cancer patients. Chemo brain is a serious enough concern for some women that it prevents them from getting treated, and while chemotherapy drugs likely have some effect on thinking, the possibility that anxiety and fatigue may play equally important roles in triggering those problems should provide some relief. That’s because these are issues that can be addressed with interventions such as meditation or relaxation exercises. “The study suggests the need to pay attention to fatigue and emphasizes for physicians something for us to work on with our patients,” says Dr. Claudine Isaacs, professor of medicine and Breast Cancer Program Clinical co-leader at Georgetown University. “There is no question that many women report changes in their short term memory recall, and find that they are not as sharp in their everyday tasks. But there are probably a lot of different factors that contribute to that, not just chemotherapy.”

Isaacs notes that in addition to the fatigue and stress associated with receiving a cancer diagnosis, the physiological change of menopause may also play a role. Chemotherapy can trigger menopause, which is associated with changes in memory and fuzzier thinking.

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Cimprich plans to follow the women in the study for at least a year to answer other questions such as why some of them are more prone to the cognitive changes than others, and why the muddled thinking clears up relatively soon after chemotherapy for some. “We’re looking for a way to help, and maybe manage some of these problems a little better,” she says.

22 comments
ibap
ibap

"...menopause, which is associated with changes in memory and fuzzier thinking."  So we have ads for men with "Low-T" but we tell women to give up all of their hormones.  Sounds like this is coming from the male medical establishment - the same people who brought you Viagra.

chemobrainfog
chemobrainfog

@fastercures Ahhh, yes. There will be a blogpost, likely tomorrow! Went right from #P4C2012 to #SABCS. Saw this presented. Plenty to say!

JoelStuartW
JoelStuartW

20 YEARS FROM TODAY IT WILL COME OUT THE SOME PEOPLE NEEDED CHEMO, BUT MILLIONS OF OTHERS SHOULD HAVE NEVER BE GIVEN IT.   STAGE 1-3 NO WAY.    

JoelStuartW
JoelStuartW

all stress accepted, the chances of CHEMO ( A poison) being run thru the blood system which  t r a v e l s  directly to the brain and heart can have a effect on both.   For ANY person is from stage 1-3, THIS SHOULD -NOT-BE AN OPTION.

the jokes on here may tell u different but are WRONG!

make no mistake about it. drug chemo  sales people know of this story, and are likely on this VERY board posting words to deflect story! 

AntonioCiseri
AntonioCiseri

The stress and fatigue of grief causes similar cognitive deficits. It's no surprise that the stress of a cancer diagnosis, along with a pending regime of chemo/surgery/radiation would bring about a cognitive deficit. It makes perfect sense.

shelbe_deee
shelbe_deee

@TIMEHealthland considering it kills all cells in the body, yes.

jostephan
jostephan

@TIMEHealthland Chemotherapy is to blame for total health decline in cancer patients across the board ;)

sinclatg
sinclatg

@TIMEHealthland from experience it is both. And you can't forget the pain narcotics some patients get

JoelStuartW
JoelStuartW

remember: The drug companies that make these chemo drugs, are going to PUT OUT THERE that it is likely STRESS!

 They make fortunes of of them. Chemo often is NOT the way to go.....    

 Surgery & Radiation are more often the gold standard in many situations that arise!

DiamonDie
DiamonDie

@Vansteenwinckel It's not too long since "chemo brain" was vigorously denied to exist at all...

Hadrewsky
Hadrewsky

@JoelStuartW 

And as for your medical advice your credentials are so pathetic i wouldnt follow your advice to treat a bloody nose...

You are unqualified and have half the brain of an oncologist... leave cancer treatment to those whom are not total morons.

Hadrewsky
Hadrewsky

@JoelStuartW \

again

Evidence points to stress -  your hatred of pharm companies makes you ignore the evidence.... typical thinking for the average american without the ability to process new data.In other words evidence changes minds.... cept the sheep whom already had made up their minds to ignore evidence.

Sheep like yourself would rather blame the "evil drug companies" rather than hard data rammed up your  behind.

Vansteenwinckel
Vansteenwinckel

@DiamonDie really? I suppose there's both: the pre- (and post-)chemo cognitive effects and the added effects during chemo

JoelStuartW
JoelStuartW

@Hadrewsky @JoelStuartW 

I know oncologist and a TOP sarcoma doc in nyc with 40 years experince U JOKE!

U look like a MALE NURSE DUDE!         I am not who u may need to perceive i am.

one one of us here had cancer and are am vastly superior to you dude.   

keep telling people to tak e CHEMO and you may hurt their brains and even KILL THEM!

DiamonDie
DiamonDie

@Vansteenwinckel Yes. And this article seems to me to be a bit in a similar vein. Can't be the drugs, must be "stress".

Hadrewsky
Hadrewsky

@DiamonDie 

Evidence points to stress your hatred of pharm companies makes you ignore the evidence.... typical thinking for the average american without the ability to process new data.

In other words evidence changes minds.... cept the sheep whom already had made up their minds.

Vansteenwinckel
Vansteenwinckel

@DiamonDie yep, whereas cogn dysf probably is directly cancer-related itself, just like cancer-related fatigue