Effort-reward-imbalance and overcommitment are associated with hypothalamus-pituitary-adrenal (HPA) axis responses to acute psychosocial stress in healthy working schoolteachers

In this study, we examined HPA axis responses to acute psychosocial stress in retation to effort-reward-imbalance (ERI) and overcommitment (OC) to test whether chronic stress at work is accompanied by attered HPA axis stress responses in teachers. According to Siegrist's work stress model, ERI reflects stress due to a tack of reciprocity between personal costs and gains at work, whereas CC is conceptualized as a personality trait mainly characterized by the inability to withdraw from work obligations. Fifty-three medication-free, non-smoking, healthy teachers (33 women, 20 men, 29-63 years, mean age 49.9 +/- 8.58 years) were confronted with the Trier Social Stress Test (TSST), a widely used standardized stress protocol to induce acute psychosociat stress in the laboratory. ACTH (five samples), total plasma (six samples) and free salivary cortisol (eight samples) were repeatedly measured before and after challenge. In the total group, ERI and OC were only marginally associated with HPA axis responses to acute stress. However, in the subgroup of responders (N = 30) high levels of OC were significantly associated with lower ACTH (p = 0.03) as well as plasma (p = 0.02) and salivary cortisol (p < 0.001) responses and results remained significant controlling for depressive symptoms. When additionally controlling for acute perceived stressfulness of the TSST, significant associations between OC and HPA axis responses emerged in responders as welt as the total study sample. In respect to ERI, higher stress levels were solely related to significantly stronger plasma cortisol increases after TSST exposure, but this effect became non-significant controlling for depressive symptomatology. In sum, our findings support the notion of HPA axis hyporeactivity in highly overcommitted schoolteachers. (C) 2008 Elsevier Ltd. All rights reserved.