Paul Basilio, MDLinx | September 22, 2017
A pilot study conducted by researchers at the University of California, San Diego School of Medicine has shown that breast cancer survivors who engage in increased physical activity can more than double their post-treatment mental processing speed.
Approximately three-quarters of breast cancer survivors report cognitive difficulties following treatment; some difficulties can last for years. There are currently few science-backed options for these patients.
This 12-week, randomized trial involved 87 women. Half of the women were enrolled in a physical activity intervention program tailored to individual interests and abilities; wearable activity devices were incorporated into the program. The control group received emails regarding women’s health topics, healthy eating, stress reduction, and general brain health.
“Whether or not they receive chemotherapy, many breast cancer survivors experience a decline in brain function that impacts memory, thinking and concentration,” said Sheri Hartman, PhD, Assistant Professor in the Department of Family and Preventive Medicine, and Co-Director of the Diet and Physical Activity Shared Resource at UC San Diego Moores Cancer Center. “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. This study supports the idea that exercise could be a way to help improve cognition among breast cancer survivors.”
Changes in cognition were evaluated at the start and end of the 12-week period. Analysis involved the National Institutes of Health (NIH) Toolbox Cognition Domain—a computer-based test of cognitive abilities—and the Patient Reported Outcomes Measurement Information System for self-reporting brain function abilities and problems.
This is the first completed randomized controlled trial using both a test of cognition and a self-reported method to assess the impact of physical activity on cancer survivors.
Results showed that the women in the exercise group had more than double the improvements in processing speed vs the control group. Women in the exercise group who were two years or less from diagnosis were four times more likely to show improvement in this area. Processing speed measures how fast information can be taken in and used.
Women in the intervention arm also had three times the improvements in self-reported cognition abilities when compared with the control group.
“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,” Dr. Hartman said.
While the tests evaluated several aspects of cognition, only processing speed showed a significant improvement. Researchers recommend larger and longer trials that evaluate the duration of exercise and intensity of activities to determine if increased physical activity might impact other areas of cognition.
Before the start of the study, all participants wore a research-grade accelerometer on their hips for seven days to measure physical activity at baseline and again for the last seven days of the trial to compare changes in minutes of moderately intense activity.
During the study period, women in the exercise arm used an activity tracker. Data was sent to researchers to extract activity levels and to provide feedback and encouragement to engage in at least 150 minutes of moderate-to-vigorous physical activity per week, as recommended by the NIH. Researchers provided support through phone calls and emails.
“Survivors often report that their thinking is slower or feels more foggy. The brain just doesn’t work at the same level as before cancer treatment,” said Hartman. “By providing a program with support, women are more likely to make difficult behavioral changes that lead to an increase in physical activity.”
The intervention program led to an approximately 100-minute increase in weekly physical activity in the participants in the exercise arm.
Participants were enrolled in the study between February 2015 and July 2016. To be eligible, women needed to be between 21 and 85 years of age and have been diagnosed and treated for breast cancer no more than five years before enrollment in the study.
Participants were predominantly well-educated, non-Hispanic white women. Future research in cancer populations with greater diversity is needed, the authors said.
To read more about this study, click here.