Association of Depressive Symptoms with Perceived Stress and Proinflammatory Cytokines in Treatment-Naïve Patients with Breast Cancer

Objectives: This study aimed to explore the levels and associations among depressive symptoms, perceived stress, and proinflammatory cytokines (interleukin-1β, interleukin-6, and tumor necrosis factor-α) in treatment-naïve patients with breast cancer. Methods: A cross-sectional study with one case and two control groups. Patients with breast cancer, matched patients with depression, and matched healthy women completed questionnaires and blood collection between May 2015 and March 2017. Data were analyzed using the general linear model and linear regression model. Results: The severity of depressive symptoms and perceived stress among patients with breast cancer was significantly higher than that in healthy controls and lower than those in patients with depression. Interleukin-1β was lower in patients with breast cancer than the other two groups. Perceived stress was independently and positively associated with depressive symptoms in patients with breast cancer. There were no significant associations between cytokines and depressive symptoms. Conclusion: Women with breast cancer experienced increased perceived stress prior to anticancer treatment, which was a strong contributor to severe symptoms of depression. Results emphasize the need to screen and identify patients with high perceived stress shortly after the disclosure of the diagnosis of breast cancer. Further research in larger sample is needed to investigate the relationship between proinflammatory cytokines and depressive symptoms.