Stress Reactivity Among African American Breast Cancer Survivors

Despite increased access to early detection and the availability of more effective therapeutic strategies, African American women continue to experience excess rates of morbidity and mortality from breast cancer. An emerging hypothesis about breast cancer disparities is that social conditions and physiological responses to social stressors influence biological processes that are important to the initiation and progression of disease. This hypothesis is based on data from animal studies which have shown that rats that are exposed to social stressors such as isolation are likely to develop mammary tumors that are histologically and etiologically similar to those that develop among African American women. The HPA axis plays a central role in regulating the physiological stress response; dysregulation of the HPA has been suggested as a mechanism through which social and biological factors contribute to racial disparities in breast cancer outcomes. Many African Americans experience stressful life events and circumstances, including economic, discriminatory, and other stressors. These social factors may contribute to an increased risk of advanced stage disease, but not all African American women who are exposed to adverse social factors develop advanced stage disease and those who have a limited number of psychosocial stressors can develop advanced stage breast cancer, regardless of early detection. This may be because stress reactivity, or one's physiological and psychological responses to a stressor, is highly individualized and dependent on psychological and social determinants as well as genetic factors. But, these biological and psychosocial pathways have not been examined among women at increased risk for disparities. Therefore, this study will characterize stress reactivity and emotional regulation among African American breast cancer survivors and measure the association between these responses and decisions about cancer control and treatment compliance. As part of providing empirical data on biological and psychological pathways that contribute to breast cancer disparities, the investigator's study will identify novel intervention targets that can be used to improve self-management in a population that is at risk for limited cancer control.

Dysregulation of the HPA has been suggested as a mechanism through which social and biological factors contribute to racial disparities in breast cancer outcomes.The HPA axis plays a central role in regulating the physiological stress response;a prolonged and elevated glucocorticoid (GC) response following a social stressor predicts tumor growth rates and the development of mammary cancer in rats that histologically and etiologically resembles human disease.Many African Americans experience stressful life events and circumstances, including economic, discriminatory, and other stressors. These psychosocial factors may contribute to an increased risk of advanced stage breast cancer among African American women, but not all African American women who are exposed to adverse psychosocial and social stressors develop advanced stage breast cancer and African American women who have a limited number of stressors also develop advanced stage breast cancer, regardless of early detection. This may be because stress reactivity, or one's physiological and psychological responses to a stressor, is highly individualized and dependent on psychological and social determinants. However, empirical data are not available on stress reactivity among African American breast cancer survivors and how these reactions vary among women based on their exposure to chronic stressors and psychological characteristics. Empirical data are also lacking on the association between stress reactivity and cancer control behaviors among African American breast cancer survivors even though prior studies have shown that these women are less likely than whites to engage in health behaviors that are important to cancer control and research is now being conducted to understand how stress affects these behaviors.This research is testing the hypothesis that stress: (1) promotes temporal discounting; (2) has an adverse effect on self-efficacy, and (3) reduces executive functioning (e.g., goal setting, planning). However, stress reactivity, and the association between these responses and cancer control behaviors (e.g., diet, physical activity, and treatment compliance), have not been examined among African American breast cancer survivors. Prior studies have shown that African Americans have a dysregulated stress response as a result of persistent exposure to chronic and acute and stressors; this may alter stress responses and lead to high levels of allostatic load. In order to develop effective behavioral interventions for African American breast cancer survivors, an important first step is to verify that the mechanisms (e.g., temporal discounting, self-efficacy) involved in health behaviors for cancer control (e.g., diet, physical activity, treatment compliance) are associated with stress reactivity among these women. Therefore this study will characterize stress reactivity among African American breast cancer survivors and validate the association between these responses and targeted mechanisms of behavior change.