The Psychological Resilience of Older Adults Is Key to Their Independence in Instrumental Activities of Daily Living and Social Participation.

: The link between stress and performance in instrumental activities of daily living (IADLs) and participation in older adults is gaining importance. The existing evidence is based on single measures of salivary cortisol levels; therefore, there is a need for more comprehensive studies that incorporate long-term measurements of cortisol concentrations as indicators of chronic stress. In consequence, the objective is to determine whether perceived stress, hair cortisol concentration, and psychological resilience are related to IADLs and participation in older individuals. : A sample of 63 individuals with a mean age of 76.5 years underwent an assessment of stress variables (Perceived Stress Scale, hair cortisol concentration, and Resilience Scale), IADLs (UPSA Scale), and participation (PART-O Scale). Using the stress variables as factors, multiple linear regressions were conducted to predict UPSA and PART-O scores and their respective subscales. The correlation between UPSA and PART-O was also examined. : After controlling for age, gender, and cognitive status, resilience emerged as the sole independent predictor of overall scores on both scales, as well as on two subscales: UPSA-Communication and PART-O-Others, for which hair cortisol was also a predictor. The effect size of the association between UPSA and PART-O scores was small. : psychological resilience is not only a protective variable against stress but also appears to be associated with instrumental functioning and social participation in older adults. This finding suggests that resilience plays a role in facilitating IADLs and participation among the elderly population.