Simplifying the energy balance message for breast cancer prevention

BMI, physical activity, and breast cancer subtype in white, black, and Sea Island breast cancer survivors

Higher BMI, lower rates of physical activity (PA), and hormone receptor-negative breast cancer (BC) subtype are associated with poorer BC treatment outcomes. We evaluated the prevalence of high BMI, low PA level, and BC subtype among survivors with white/European American (EA) and African American (AA) ancestry, as well as a distinct subset of AAs with Sea Island/Gullah ancestry (SI). We used the South Carolina Central Cancer Registry to identify 137 (42 EAs, 66 AAs, and 29 SIs) women diagnosed with BC and who were within 6-21 months of diagnosis. We employed linear and logistic regression to investigate associations between BMI, PA, and age at diagnosis by racial/ethnic group. Most participants (82%) were overweight/obese (P=0.46). BMI was highest in younger AAs (P=0.02). CDC PA guidelines (≥150min/week) were met by only 28% of participants. The frequency of estrogen receptor (ER)-negative BC subtype was lower in EAs and SIs than in AAs (P<0.05). This is the first study to identify differences in obesity and PA rates, and BC subtype in EAs, AAs, and SIs. BMI was higher, PA rates were lower, and frequency of ER-negative BC was higher in AAs as compared to EAs and SIs. This study highlights the need to promote lifestyle interventions among BC survivors, with the goal of reducing the likelihood of a BC recurrence. Integrating dietary and PA interventions into ongoing survivorship care is essential. Future research could evaluate potential differential immune responses linked to the frequency of triple negative BC in AAs.

Disparities in Obesity, Physical Activity Rates, and Breast Cancer Survival

The significantly higher breast cancer (BCa) mortality rates of African-American (AA) women compared to non-Hispanic (NHW) white women constitute a major US health disparity. Investigations have primarily focused on biological differences in tumors to explain more aggressive forms of BCa in AA women. The biology of tumors cannot be modified, yet lifestyle changes can mitigate their progression and recurrence. AA communities have higher percentages of obesity than NHWs and exhibit inefficient access to care, low socioeconomic status, and reduced education levels. Such factors are associated with limited healthy food options and sedentary activity. AA women have the highest prevalence of obesity than any other racial/ethnic/gender group in the United States. The social ecological model (SEM) is a conceptual framework on which interventions could be developed to reduce obesity. The SEM includes intrapersonal factors, interpersonal factors, organizational relationships, and community/institutional policies that are more effective in behavior modification than isolation from the participants' environmental context. Implementation of SEM-based interventions in AA communities could positively modify lifestyle behaviors, which could also serve as a powerful tool in reducing risk of BCa, BCa progression, and BCa recurrence in populations of AA women.