Effort reward imbalance, and salivary cortisol in the morning

Effort reward imbalance (ERI) is suggested to increase risk for stress and is hypothesized to increase cortisol levels, especially the awakening cortisol response, ACR.

In 2006 and 2008, 480 individuals collected saliva samples at awakening and 30 min post-awakening. Mixed effects models with subject as a random effect and appropriate covariates were used to evaluate associations between the Effort Reward Model, and salivary cortisol at awakening (S0), and ACR.

ERI was negatively and significantly associated with S0 for women and positively associated with ACR. S0 and ACR increased significantly from 2006 to 2008.

ERI was significantly associated with cortisol levels at awakening (inverse association) for women, and positively associated with ACR. The population experienced a significant increase in morning cortisol levels and ACR from 2006 to 2008, which may originate in a re-organization of the included work places.