Study Demonstrates the Role of Cortisol in the Early-Stage Breast Cancer Patients’ Quality of Life

Breast cancer is the most common type of cancer in women. Approximately 287,850 women in the United States will be diagnosed with breast cancer in 2022. Along with survival, quality of life— which encompasses physical, emotional, social, and functional health—is among the top concerns of women living with breast cancer and undergoing treatment. Quality of life is related to many clinical factors, including disease stage, type of treatment, symptoms, adverse events (AEs) and function, as well as sociodemographic factors (e.g., younger age, less education, unemployment, and lower income).

Cortisol is a stress hormone involved in regulating mood, energy, stress, and immune function. If exposed to stress, the body’s cortisol levels may become dysregulated, leading to impaired physical and emotional health. Most research exploring cortisol in patients with cancer is conducted in patients with late-stage breast cancer. To better understand the role of cortisol and quality of life in patients with early-stage breast cancer, Pereira and colleagues from the University of Minho–Braga in Portugal analyzed patients’ cortisol levels and several quality-of- life measures. Their results were published recently in Cancer Nursing and demonstrate the role of cortisol in moderating the relationship between AEs and quality of life in patients with early-stage breast cancer.

Study participants were identified during postsurgery consultation in the breast cancer clinic. After the chemotherapy teaching visit, consent was obtained from interested patients to participate in the study. A total of 112 patients with early-stage breast cancer and a mean age of 53 years enrolled in the study.

The study was guided by the Model of Psychosocial Adaptation to Chronic Disease which guided the researchers’ selection of measurement tools and planned analyses. Quality-of-life measures included the European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC-QLQ), a breast cancer–specific symptom questionnaire, the Illness Perception Questionnaire–Brief, the Cancer Behavior Inventory-Brief, and the Hospital Anxiety and Depression Scale (HADS). Cortisol was assessed by examining saliva samples taken by study participants at specific times the night before and several times the day of treatment.

The results demonstrated that participants’ quality of life was associated with higher cancer stage, more treatment-related AEs, and more threatening illness perceptions. By far, the largest contributing factor to quality of life was AEs. Quality of life was not associated with psychological health or self-efficacy for coping. Cortisol significantly mediated the relationship between AEs and quality of life.

The researchers noted that cancer stage and AEs can contribute to worse quality of life, mainly owing to more prominent disease burden and interference with daily living. They also explain how perceiving breast cancer as more threatening can exacerbate the symptoms patients are experiencing, thus leading to even worse quality of life. On the other hand, when patients perceive their cancer as not being threatening, they are more likely to engage in coping behaviors and have positively balanced emotional responses to their cancer.

The moderating function of cortisol levels directly impacted the strength of the relationship between AE and quality of life. When patients’ cortisol levels were lowest (measured by the nadir), the relationship was stronger, and quality of life was higher. The researchers explain how low levels of cortisol represent normal immune system function. On the other hand, when cortisol levels were high, patients’ immune system were suppressed, which is associated with worse treatment effects and impaired quality of life.

The researchers note the cross-sectional nature of this study prevents analyzing the cumulative effects of AEs, cortisol, and quality of life. Still, these results indicate the need for more research assessing the role of stress and cortisol on patients’ well-being. Understanding the role of cortisol can help identify biologic and behavioral targets to address patients’ stress, and potentially address the compound nature of cortisol’s impact on other outcomes.

For oncology nurses, understanding the relationships between patients’ quality of life, AEs, and other indicators like cortisol can clarify how and when to intervene to support patients’ well-being. Patients in this study were assessed during their second chemotherapy session, but these relationships evolve over the course of treatment and into survivorship. Because oncology nurses often have close insights into patients’ stress levels and well-being, they can identify patients who are at risk for poor quality of life and suggest interventions and referrals to address the factors that contribute to patients’ well-being.

Reference

Quality of Life in Women with Breast Cancer Receiving Chemotherapy and the Moderating Role of Cortisol