Exhaustion-related changes in cardiovascular and cortisol reactivity to acute psychosocial stress

Prior findings indicate that individuals scoring high on vital exhaustion show a dysfunctional stress response (DSR), that is, reduced cortisol reactivity and habituation to psychosocial stressors. The main aim of the present study was to examine whether a DSR may be a vulnerability factor in exhaustion disorder (ED). We examined whether a DSR is present during the early stages of ED, and still is present after recovery. Three groups were studied: 1. Former ED patients (n=14); 2. persons who during the past 6 month had experienced stress at work and had a Shirom-Melamed Burnout Questionnaire (SMBQ) score over 3.75, considered to indicate a pre-stage of ED (n=17); 3. persons who had not experienced stress at work during the past 6 months and had a SMBQ score below 2.75 (n=20). The participants were exposed twice to a virtual version of the Trier Social Stress Test (V-TSST), during which salivary cortisol samples were collected. In addition, high frequency heart rate variability (HF-HRV), heart rate (HR), t-wave amplitude (TWA), and α-amylase were assessed to examine stress reactivity and habituation in the autonomic nervous system (ANS). The initial analyses showed clear hypothalamic-pituitary-adrenal (HPA) axis and sympathetic nervous system (SNS) activations in both V-TSST sessions, together with habituation of cortisol and heart rate in the second session, but without any significant group differences. However, the former ED patients showed considerable variation in self-reported signs of exhaustion (SMBQ). This led us to assign former ED patients with lower ratings into the low SMBQ group (LOWS) and those with higher ratings to the high SMBQ group (HIGHS). When repeating the analyses a different picture emerged; the HIGHS showed a lower cortisol response to the V-TSST than did the LOWS. Both groups' cortisol response habituated to the second V-TSST session. The ANS responses did not differ between the two groups. Thus, persons in a pre-stage of ED and unrecovered former ED patients showed signs of DSR, in contrast to healthy controls and recovered former ED patients. The results may be interpreted as indicating that DSR in the HPA axis is present early on in the stress process, but subsides after successful recovery.