Abstract

Work stress is a major risk factor of disease burden, causing enormous productivity and economic loss. Short- and medium- term effectiveness (up to 3 years) of stress management intervention (SMI) in the workplace has been demonstrated, yet long-term effectiveness is unknown. 94 middle management male employees participated in a randomised wait-list controlled trial with 9-„year follow-up (2006–2015), and all of them received SMI intervention during the first two years. The SMI program included two interventions tightly based on the Effort-Reward Imbalance (ERI) model: the situation-specific component for mismatch between effort and reward; and the person-specific component termed over-commitment. The intervention used psychodynamic principles as well as cognitive behavioural techniques. The primary outcome was the ERI indicators for work stress, and the secondary outcome was depressive symptoms for mental health. In addition, an external control group (n = 94) was used for comparison purpose. Within the intervention group, work stress (E-R ratio and over-commitment) and depressive symptoms were significantly improved during the intervention period (2006–2008) (p < 0.001); then work stress remained relatively stable during the posttrial-follow-up (2008–2015), whereas depressive symptoms climbed back. Comparative analyses with the external control group, using multilevel modelling, revealed a significantly more favourable development regarding work stress and depressive symptoms in the SMI group (p < 0.05). in conclusion, long-term (i.e. 9-year) effectiveness of a SMI at work based on the ERI model, with psychodynamic as well as cognitive behavioural techniques, was observed, indicating beneficial effects on work stress reduction and mental health improvement.