Physical Activity May Help With ‘Chemo Brain’ in Breast Cancer

Moderate-to-vigorous exercise before and during chemotherapy for breast cancer may help with cancer-related cognitive decline, highlighting the importance of physical activity throughout treatment.

Patients with breast cancer who completed at least 150 minutes of moderate-to-vigorous physical activity per week before and during chemotherapy had better cognitive function once they completed treatment.

The benefit of physical activity related to cognitive function persisted for six months after chemotherapy completion, according to the study published in the Journal of Clinical Oncology.

“Cancer-related cognitive decline is a growing clinical concern and it's very common, most patients will experience some degree of cognitive deficits throughout their cancer experience. … We call it chemo brain. It's important for us to identify methods of preventing this decline, if possible. And, ideally, those methods will be cost effective and easy for patients to do,” Elizabeth Salerno, an assistant professor of surgery in the division of public health sciences at Washington State University School of Medicine in St. Louis, Missouri, said in an interview with CURE®. Salerno was the lead author on the study and also holds a post doctorate in kinesiology with an emphasis in exercise psychology.

Cancer-related cognitive decline, or “chemo brain,” can present differently depending on the patient, according to Salerno. Common symptoms include fogginess, difficulty concentrating and forgetfulness.

In the study, Salerno and other researchers measured physical activity and cognitive function before and during chemotherapy, and then six months after treatment was completed. “We saw a robust association between high levels of pre-chemotherapy physical activity, as well as maintaining high levels of physical activity during chemotherapy, with better cognitive function over time,” Salerno explained.

Some of the most common methods of physical activity reported by patients from the study included walking, household chores and gardening. “I think that really speaks to opportunities to be physically active in a patient's daily life.There are numerous ways to increase activity levels that don't necessarily have to look like the traditional exercise regimen,” she added, noting that patients with cancer who are considering starting a new exercise regimen should consult with their physician first.

Parking farther away from the grocery store and walking up the steps instead of taking the elevator are two other ways to easily implement more exercise into daily life. Patients can also discover other ideas from their health center and survivorship program.

Salerno did note, however, that the strongest association they saw for cognition in this study was with moderate-to-vigorous physical activity. To determine the intensity of physical activity, she recommended the “talk test.” “If the patient is exercising at a moderate intensity, they can hold a conversation while they're exercising, but they can't sing. It moves to vigorous exercise is when it's difficult to still hold a conversation while exercising. So that's a nice gauge for patients to identify the intensity of their exercise,” she explained.

During COVID-19, when immunocompromised patients strive to be active in a socially distanced and safe way, Salerno recommended trying different activities. These can include using objects around the house as weights (laundry detergent bottles, soup cans, gallon water jugs) for muscle strengthening routines or playing with the dog in the backyard.

“The only other thing I should say about trying to be active in the middle of a pandemic is for patients to show themselves grace,” she concluded. “Oftentimes, as we work towards a new health behavior, our progress is never linear, so there will be setbacks. … Right now, with the pandemic, we are facing all of these challenges together, and so being patient with ourselves and others is important.”

For next steps in this study, Salerno said that randomized controlled trials would be important to confirm whether intervening with physical activity before or during chemotherapy could improve cognition.

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