Yale researchers examine how exercise may alleviate side effects of breast cancer treatment

A growing body of evidence supports the association between lifestyle behaviors and the risk for breast cancer, as well as outcomes after a diagnosis.

HemOnc Today spoke with Melinda L. Irwin, PhD, MPH, professor of epidemiology at Yale School of Public Health and associate director of population sciences at Yale Cancer Center, about research efforts at the institution designed to assess how exercise can alleviate side effects caused by breast cancer treatment.

Melinda L. Irwin

Question: How long has Yale’s research focused on assessing exercise as an intervention for the side effects of breast cancer treatment?

Answer: The research we have conducted during the past 15 years is looking at exercise, weight management and healthy eating in breast cancer, specifically on how lifestyle factors impact biological markers. We know from observational studies that higher levels of exercise are associated with a lower risk for developing and dying of breast cancer, as well as other malignancies such as colorectal cancer. During the past 10 to 15 years, my colleagues and I have been conducting randomized controlled interventions looking at what mechanisms in the blood change due to exercise. We also have another study where we are collecting breast tissue to see how breast tissue level changes may be impacted by weight loss. Our research efforts have provided evidence-based counseling at the Yale Cancer Center Survivorship Clinic for all patients diagnosed with cancer.

Q: What makes your research efforts unique?

A: One of our recent studies, published in 2015 in Journal of Clinical Oncology, looked at women with breast cancer who were taking aromatase inhibitors and were experiencing side effects from treatment. Results showed that exercise improved one of the most common side effects — joint pain. We found exercise led to a 30% improvement in this very common side effect, which is associated with stopping the medication. Most of the studies that had been conducted prior to this one did not specifically look at women taking aromatase inhibitors, and more than 50% of women diagnosed with breast cancer will be recommended to take aromatase inhibitors. Side effects that lead to poor medication compliance are common, and in turn adversely affect prognosis. We hope to show in our next study that exercise and weight management improve medication adherence by preventing medication side effects.

Q: How has your research impacted the health of breast cancer patients outside of clinical studies?

A: We had another paper published in Journal of Clinical Oncology in which we looked at the effect of a weight loss intervention on numerous endpoints. We compared telephone vs. in-person counseling vs. usual care. We showed that telephone counseling was just as effective as in-person counseling, which really helps with the accessibility of these interventions so that they can be done via telephone all over the country. The reach is broader and barriers related to time and access are improved.

Q: How have research efforts changed with time?

A: When I started my career, 15 years ago, most of the research being conducted looked at how to prevent cancer. Now, given improvements in treatment and the increased survival rate, I was really interested to examine how lifestyle interventions could improve prognosis. In particular, one of my publications that came out during the mid-2000s looked at changes in physical activity levels from before to after a breast cancer diagnosis. We showed that those who were inactive before their diagnosis but became physically active after their diagnosis significantly reduced their risk for breast cancer mortality compared with those who did not change their exercise levels. This is a very important message that suggests it is never too late to change your exercise levels and other lifestyle behaviors.

Q: What are some of the research challenges you have faced?

A: One of the challenges we have faced is with patients reverting back to their prior lifestyle behaviors a year or two later after our studies end. A challenge has been in trying to maintain favorable behavior changes in these patients and identifying what barriers prevent maintenance of favorable behavior changes. Also, what clinical opportunities can we provide for them in order to maintain healthy behaviors?

Q: What future research efforts are on the horizon?

A: One major area of our future research is looking at how exercise and weight management improve medication adherence and then also looking at early interventions in patients at the time of diagnosis. We know that weight itself and weight gain on top of that adversely affects prognosis. If we can prevent weight gain by promoting these healthy eating and exercise interventions at diagnosis and through treatment, this would be really significant because most interventions today occur after treatment.

Q: Do you have any final thoughts?

A: We also completed a study looking at the Livestrong at the YMCA program, which is a great program where the Livestrong Foundation partnered with YMCAs across the country to offer free, 3-month, twice-weekly exercise programs to all cancer survivors. They are led by certified personal trainers at YMCAs across the country and this is a really great program. We tested the safety and efficacy of the program and we found that it was safe and effective in favorably changing physical activity, fitness and improved fatigue and quality of life. I really encourage physicians and oncologists to refer their patients to this program. – by Jennifer Southall

For more information:

Melinda L. Irwin, PhD, MPH, can be reached at Yale School of Public Health, 60 College St., P.O. Box 208034, New Haven, CT 06520; email: melinda.irwin@yale.edu.

Disclosure: Irwin reports no relevant financial disclosures.