Stress and resilience: cortisol hypo-response to acute stress in non-resilient individuals

Resilience-the outcome of effective adaptation to adversity-is a dynamic construct referring to the preservation or quick recovery of mental health in the face of significant stressors. Despite the crucial role of the acute stress response in coping with adversity, no consensus exists regarding its relationship with resilience. Inconsistent findings may be due to variability in the assessment of resilience. The present study investigates the relationship between resilience and acute stress responses by comparing resilient and non-resilient individuals in their responses to experimentally induced acute stress. A novel approach was used, combining the Socially Evaluated Cold Pressor Test (SECPT) as a reliable and replicable stress induction method with a uniquely characterized sample whose resilience had been assessed in a prior longitudinal study. Based on these longitudinal assessments of stressor reactivity, participants (N = 48) were classified as resilient (14 female / 10 male; age in years: M = 34.5, SD = 9.32) or non-resilient (17 female / 7 male; age in years: M = 31.6, SD = 5.52). Salivary cortisol and subjective measures (subjective stress and State Anger) were assessed before and 20 min after stress induction. Resilience was associated with cortisol reactivity, with non-resilient participants showing significantly lower cortisol responses to the SECPT compared to the resilient participants (F(1,45) = 4.252, p= 0.045). Subjective measures did not differ between groups in terms of reactivity. However, non-resilient participants reported higher overall levels of subjective stress (F(1,43) = 4.780, p= 0.034). It remains to be clarified whether resilience determines cortisol reactivity or whether cortisol reactivity represents a mechanism underlying resilience.