Randomized Trial: Rehab Program Improves 'Chemo Brain'

Pam Harrison

November 01, 2016

Patients who experience cognitive symptoms after chemotherapy appear to respond well to a web-based rehabilitation program that not only improves cognitive symptoms but also lessens anxiety, depression, fatigue, and stress, a randomized trial indicates.

"Up to 70% of cancer survivors report that their cognitive function is not as good as it was prior to their cancer diagnosis and this impacts their quality of life and daily functioning," study coauthor Janette Vardy, MD, Concord Cancer Centre, New South Wales, Australia, told Medscape Medical News in an e-mail.

"And there are no proven treatments for cancer-induced cognitive impairment," she said.

"To the best of our knowledge, this is the largest cognitive intervention study that has shown a benefit for patients who are reporting persistent cognitive symptoms following chemotherapy," lead author Victoria Bray, MD, PhD candidate, University of Sydney, Australia, added in a statement.

This is the largest cognitive intervention study that has shown a benefit for patients. Dr Victoria Bray

The study was published online October 28 in the Journal of Clinical Oncology.

A total of 242 participants, 95% of whom were female and 89% of whom had been treated for breast cancer, were assigned to the web-based cognitive rehabilitation program or to standard oncology care.

All patients had completed three or more cycles of adjuvant chemotherapy some time within the previous 6 to 60 months, and all reported persistent cognitive symptoms.

The mean time since patients had finished their chemotherapy was 27 months.

"Both groups received a semi-structured, 30-minute telephone consultation discussing compensatory strategies aimed at helping their cognitive symptoms," Dr Vardy explained.

However, the intervention group was also assigned to Insight, a computerized neurocognitive learning program that uses adaptive exercises targeting processing systems to improve cognition.

"The recommended training time was four 40-minute sessions/week for 15 weeks, for a total of 40 hours," Dr Bray noted.

The primary outcome was self-reported cognitive function as assessed by the Functional Assessment of Cancer Therapy Cognitive Function version 3 (FACT-COG) questionnaire.

Significant Differences

On completion of the program, participants who had been randomly assigned to the active intervention group demonstrated significant differences in all FACT-COG subscales compared with controls.

Table. FACT-COG Differences in Perceived Cognitive Impairment

Variable 15 Weeks After Insight Intervention (Difference Between Insight and Control Groups) P Value 6 Months After Insight Intervention P Value
FACT-COG PCI –7.47 <.001 –6.48 .001
Perceived cognitive abilities 3.34 <.001 2.88 <.001
Less impact on quality of life from PCI –1.20 .02 –1.0 .06
Fewer comments from others suggested they had cognitive impairment –0.71 .04 No difference between intervention and controls  

PCI = perceived cognitive impairment.


At the end of the intervention, there were no between-group differences in global quality of life.

However, quality of life 6 months after completion of the program was better in the intervention group than in the controls. Levels of perceived stress were also lower in the Insight group.

In contrast, investigators observed no differences between the two groups on neuropsychological function tests either after completion of the intervention or 6 months later.

As Dr Vardy explained, the association between cognitive symptoms and objective cognitive test results is known to be poor, and the neuropsychological test battery used to assess participants in the study may not have been sensitive enough to pick up differences in cognitive functioning.

"The average training time was lower than the recommended training time and yet [the program] still produced a significant difference in cognitive symptoms that was maintained 6 months later as well as improvements in anxiety and depression," Dr Vardy observed.

"So the amount of training required may be less than previous suggested."

The Insight program has the added advantage of being home based and relatively inexpensive, as investigators point out.

Symptoms of "Chemo Brain"

As Dr Vardy observed, the most common complaints from patients who develop "chemo brain" are problems with multitasking, memory, and difficulties finding the right word.

"The majority of people report that they can perform cognitive tasks in a quiet environment where they can focus on one activity but they run into problems when they have to contend with other distractions as are encountered in real world situations," Dr Vardy observed.

For most patients, cognitive symptoms resolve upon completion of treatment, but cancer-induced cognitive impairment can last as long as 10 to 20 years in a subgroup of patients, she added.

Commenting on the study, Patricia Ganz, MD, an American Society of Clinical Oncology expert in cancer survivorship who was not affiliated with the study, emphasized that cognitive symptoms can have a "profound" effect on some patients' lives.

"Cognitive rehabilitation should be a core part of cancer survivorship care as cognitive symptoms are very common and have a profound effect on people's lives," Dr Ganz said in a statement.

"This study points to a simple tool that may help alleviate mild cognitive problems," she added.

The Insight program is available online from BrainHQ by PositScience.

Patients are able to access some of the training free of charge but need to purchase a monthly or yearly subscription to access the full suite of training at a cost of $14 a month or $96 a year.

J Clin Oncol. Published online October 28, 2016. Full text

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