Exploring Interindividual Variability in Resilience to Stress: Social Support, Coping Styles, and Diurnal Cortisol in Older Adults.

The psychobiological response to stress is known to be a key factor affecting health at any age, but especially in older adults. It involves the hypothalamic-pituitary-adrenal (HPA) axis, a hormonal circuit whose product is the activation of cortisol. We sought to explore the relationships leading to resilience to stress, as exemplified by the model of aging, stress, and resilience, in a sample of older adults at risk for mental health problems. Specifically, we examined the concurrent effects of individual age-related determinants, social support, and coping style on the cortisol awakening response (CAR), the cortisol area under the curve (AUC) with respect to ground, and the rate of change of cortisol from the awakening peak to bedtime. Our results showed an association between life impairment and health problems on the three indicators of HPA disturbance. An higher AUC was also observed in older age and in individuals reporting more major life events. Less use of avoidance coping was also associated with greater levels of CAR and AUC. Although significant, the measured determinant explained only a small part of the total interindividual variability in our three cortisol indices. Other factors, such as same-day stressors especially in older populations at risk for psychological distress, should be considered in future studies.