Childhood Adversity and Chronic Stress Influence Vagal Tone and the Proinflammatory Response to Acute Stress in Women with Breast Cancer

Abstract

We previously reported that women diagnosed with breast cancer exhibit a proinflammatory phenotype (increased behavioral symptoms and higher IL-6 levels), if exposed to childhood adversity. The purpose of this project was to determine if childhood adversity and/or chronic stress influenced vagal tone, the cortisol response, and the proinflammatory response to the Trier Social Stress Test (TSST), in women recently diagnosed with breast cancer. We hypothesized that exposure to child adversity and/or chronic stress will suppress the vagal anti-inflammatory pathway, increasing risk for greater stress-associated production of proinflammatory cytokines. Women were assessed for chronic stress and childhood adversity and completed the TSST while wearing Holter monitors to capture vagal tone. Salivary cortisol and cytokines were measured before, throughout, and after the TSST. Results revealed that women reporting greater childhood emotional abuse and neglect or chronic stress had lower vagal tone during the TSST and greater levels of cortisol and IL-6 post-TSST. Emotional neglect was associated with an exaggerated IL-6 response, while physical neglect was related to greater IL-1 beta response to the TSST. Women with greater chronic stress had higher IL-6 and IL-1 beta post-TSST. These results demonstrate that women with breast cancer exposed to greater childhood adversity and chronic stress exhibit a more intense stress-induced proinflammatory response, which may be mediated by suppression of vagal tone.