Most breast cancer patients may not be getting enough exercise

Physical activity after breast cancer diagnosis has been linked with prolonged survival and improved quality of life, but most participants in a large breast cancer study did not meet national physical activity guidelines after they were diagnosed. Moreover, African-American women were less likely to meet the guidelines than white women. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the findings indicate that efforts to promote physical activity in breast cancer patients may need to be significantly enhanced.

The US Department of Health and Human Services, as well as the American Cancer Society, recommends that adults engage in at least 150 minutes of moderate-intensity physical activity or 75 minutes of vigorous-intensity physical activity (or an equivalent combination thereof) each week for general health benefits and for chronic disease prevention and management.

Because it's important to understand whether there is capacity for improvement in the physical activity levels of women with breast cancer, Brionna Hair, a doctoral candidate in epidemiology at the University of North Carolina at Chapel Hill, and her colleagues examined levels of and changes in physical activity following breast cancer diagnosis, overall and by race, in a population-based study of breast cancer patients. The study assessed pre- and post-diagnosis physical activity levels in 1,735 women aged 20 to 74 years who were diagnosed with invasive breast cancer between 2008 and 2011 in 44 counties of North Carolina.

The researchers found that only 35 percent of breast cancer survivors met current physical activity guidelines post-diagnosis. A decrease in activity approximately six months after diagnosis was reported by 59 percent of patients, with the average participant reducing activity by 15 metabolic equivalent hours - equivalent to about five hours per week of brisk walking. When compared with white women, African-American women were about 40 percent less likely to meet national physical activity guidelines post-diagnosis, although their reported weekly post-diagnosis physical activity was not significantly different from that of White women (12 vs 14 metabolic equivalent hours). Ms. Hair noted that it's important to realize that African-American women experience higher mortality from breast cancer than other groups in the United States.

What are the key statistics about breast cancer?

Breast cancer is the most common cancer among American women, except for skin cancers. About 1 in 8 (12%) women in the US will develop invasive breast cancer during their lifetime.

The American Cancer Society's estimates for breast cancer in the United States for 2014 are:

About 232,670 new cases of invasive breast cancer will be diagnosed in women.
About 62,570 new cases of carcinoma in situ (CIS) will be diagnosed (CIS is non-invasive and is the earliest form of breast cancer).