When breast cancer survivors increased their physical activity, they more than doubled their mental processing speed, according to a study at the University of California San Diego School of Medicine.
Researchers estimate that up to 75 percent of breast cancer survivors experience difficulties with cognitive functioning after treatment, and the problems can last several years. The finding about exercise could give patients an option for dealing with cognition problems that they haven’t known about.
The team published its report in the journal Cancer under the title “Randomized controlled trial of increasing physical activity on objectively measured and self-reported cognitive functioning among breast cancer survivors: The memory & motion study.”
“Whether or not they receive chemotherapy, many breast cancer survivors experience a decline in brain function that impacts memory, thinking and concentration,” Sheri Hartman of the university’s Moores Cancer Center said in a press release. Hartman, the co-director of the center’s diet and physical activity program, was senior author of the study.
Researchers conducted the study, which involved 87 predominantly well-educated, non-Hispanic white women, between February 2015 and July 2016.
The group was split in two. One participated in an exercise program. It was personalized to match the participants’ abilities and interests. Participants wore activity devices such as research-grade accelerometers on their hips or Fitbit One activity trackers. The control arm received emails on women’s health, nutrition, stress management, and brain health.
Researchers assessed cognition at the start and end of the 12-week study period with two methods. One was the National Institutes of Health Toolbox Cognition Domain, a computer-based test of cognitive abilities. The other was the Patient-Reported Outcomes Measurement Information System, which involves patients’ self-reports of their brain function. It was the first time a study used both approaches to assess the impact of physical activity on cancer survivors.
In general, women in the exercise arm increased their weekly physical activity by about 100 minutes.
“The women who participated in the physical activity intervention experienced a significant improvement in cognitive processing speed and some improvements in their perceived mental abilities,” Hartman said. “This study supports the idea that exercise could be a way to help improve cognition among breast cancer survivors.”
Women in the exercise arm were able to take in and use information twice as fast as those in the control arm. Scientists call the measurement processing speed.
In addition, women in the exercise group who were less than two years from diagnosis were four times more likely to show improvements in processing speed than the control group. The finding suggested that starting a physical activity program as soon as possible after treatment could generate the best results.
“This is a preliminary study, but it appears that intervening closer to diagnosis may be important to having an impact, and this is the population we may need to target,” Hartman said.
Results from the self-reported cognition abilities’ measurements aligned with the computer-based results.
Women in the exercise arm reported three times the improvements in cognition than those in the control group. Improvement in processing speed stood out when compared with other cognition measures, however.
Researchers recommended conducting a larger and longer study to determine if increased physical activity could have additional effects on the brain health of cancer survivors in the long run. Greater diversity in patient population is also needed in future research, researchers said.