Abstract
Maladaptive emotion regulation and dysregulated hypothalamic-pituitary-adrenal (HPA) axis functioning are characteristic of depression and anxiety. However, little research examines whether and how emotion regulation affects HPA axis functioning. We utilized an experience sampling methodology to examine associations between three emotion regulation strategies (problem solving, disengagement, and emotional expression/support seeking) and diurnal cortisol rhythms and reactivity in everyday life. Participants were young adults with current, past, or no history of internalizing disorders (depression or anxiety; N = 182). Across participants, problem solving was associated with an elevated cortisol awakening response (CAR) while disengagement was associated with a steeper cortisol slope. Only for individuals with internalizing disorders was momentary problem solving and emotional expression/support seeking associated with higher cortisol reactivity and emotional expression/support seeking associated with a flatter diurnal slope and blunted CAR. Results provide insight into associations between emotion regulation and day-to-day HPA-axis functioning.