The thinking problems associated with cancer treatment -- often called "chemo brain" -- may sometimes be present before a person undergoes chemotherapy, according to a small new study.
The research, presented at the American Association for Cancer Research and Cancer Therapy & Research Center's San Antonio Breast Cancer Symposium, suggests that chemotherapy may not be the sole cause for cognitive problems during cancer.
Therefore, "women should not avoid accepting recommendations for lifesaving chemotherapy for fear of 'chemo brain,'" study researcher Bernadine Cimprich, Ph.D., R.N., who is an associate professor emerita at the University of Michigan School of Nursing in Ann Arbor, said in a statement.
The study included 97 women; 28 with breast cancer who received chemotherapy, 37 with breast cancer who received radiotherapy, and 32 who didn't have breast cancer. Researchers had them report how much fatigue they felt, and they also conducted fMRI brain scans on the women as they completed a memory task (in order to see their neurocognitive responses) a month before they started their cancer treatment (if applicable), and a month after they started their treatment.
Researchers found that fatigue levels were higher and accuracy on the memory task was lower among the women who underwent chemotherapy -- both before they started the chemotherapy and after -- compared with the women who underwent radiotherapy and the healthy women.
The levels of fatigue reported were strongly linked with the performance on the memory test and later thinking problems.
And before anyone received treatments, researchers found that the women with breast cancer had less functioning in the brain regions vital to performing the memory task than the healthy women. Specifically, the healthy women had the best functioning of this part of the brain, followed by the women who would go on to receive radiotherapy, followed by the women who would go on to receive the chemotherapy.
"Our initial findings showed that the level of worry interfered with patients' ability to do a task," Cimprich said in the statement. "The level of worry had a key role in the cognitive problems with these women before treatment, and this worry was related to fatigue."
Because the findings were presented at a conference and not yet published in a peer-reviewed journal, they should be regarded as preliminary. However, this isn't the first time it's been suggested that "chemo brain" symptoms may not only come from chemo.
A study published earlier this year in the Journal for Clinical Psychology in Medical Settings showed that women who had breast cancer surgery but had not yet undergone chemotherapy experienced similar memory problems as those who had undergone the treatment. The study also showed that the women who were most likely to experience these problems were also the ones who were more stressed or didn't cope with their stress in a direct way, researchers found.
And another previous study, published in the Archives of Neurology, showed that women who had survived breast cancer are more likely to experience thinking difficulties as evidenced by brain scans, with women who underwent chemotherapy being more likely to experience these thinking problems at a greater severity than others, Health.com reported.
"I have patients tell me, 'I'm just working harder and I'm slower at what I do, and I have to check my work and I still find errors, even when I'm working methodically,'" Robert Ferguson, Ph.D., who is a clinical psychologist at Eastern Maine Medical Center but who was not involved in the study, told Health.com. "This data is consistent with that anecdotal report."