• Project number: F 2318
• Institution: Federal Institute for Occupational Safety and Health (BAuA) / Duke University Medical Center / Charite Universitätsmedizin Berlin / IfADo, Leibniz-Institut für Arbeitsforschung
• Status: Completed Project

Description:

Burnout syndrome, associated with emotional exhaustion and a reduced performance, tends to be considered within the context of an excessive workload in particular. Although the current diagnostic criteria (ICD-10) do not recognise burnout syndrome as an independent clinical picture, it is closely related to the existence of symptoms of depression. While cognitive performance limitations surrounding concentration or attention are included among the criteria for the existence of a depressive episode, only a limited amount of empirical evidence exists for correlations between cognitive performance limitations and burnout syndrome and symptoms of depression or depressive syndromes. From the perspective of occupational health and safety, the question also arises as to what extent these interrelationships are conditioned or moderated by both mental strain in the world of work and individual determinants, and what consequences may be expected as regards the ability to work and functional in everyday life.

A collaborative project addressing these questions was carried out with the following partners:

• the Federal Institute for Occupational Safety and Health (BAuA), FG 3.4 Mental Health and Cognitive Performance, Berlin
• University Hospital of Tübingen Institute for Clinical Epidemiology and Applied Biometry
• Duke University USA, Duke University Medical Centre, Department Psychiatry and Behavioral Sciences
• Leibniz Research Centre for Working Environment and Human Factors, IfADo, Group on Ageing and Changes to the CNS, Dortmund

The project was completed in the form of three sub-projects, the results of which are summarised below.

Sub-project 1: Work- and individual-related determinants of vulnerability to burnout and depression (University of Tübingen)

The study addressed the influence of psychosocial factors at the workplace in connection with individual-related factors on the target variables of symptoms of depression, burnout and the ability to work. On the basis of a representative survey of 4,058 randomly selected employed persons aged between 31 and 60 years, the key findings were that

• among the influencing factors examined, the overall quantitative workload constitutes the primary risk factor for all three target variables, followed by cognitive stress and job insecurity,
• work-related factors have a stronger effect on burnout than they do on symptoms of depression,
• the quality of the management and decision latitude demonstrate mitigating effects,
• burnout is a potential mediator for the influence of the working conditions on the ability to work,
• the general expectation of personal efficacy is a protective factor,
• there is no relevant relationship between the age and mental health of the employees who took part in the survey,
• with increasing age, the ability to work decreases on average, although the differences between individual people increase,
• women demonstrate significantly more pronounced symptoms of depression,
• there is no specific difference between the genders in regard to burnout and the ability to work.

It should be pointed out, however, that because of the cross-sectional nature of the study, the results are only of a provisional nature. The review will be completed after a subsequent longitudinal phase of the project.

Sub-project 2: The relationship between psychosocial stress at work, depression and cognitive impairment (Duke University).

The influence of psychosocial working conditions, cognitive performance impairments and age together with the potential mediator of burnout was examined with respect to the target variables of symptoms of depression and the ability to work. For this study, 402 nurses in a health care institution in the USA were examined each month over a period of one year. The present study therefore provides the basis for a cross-validation of the findings from the sub-projects completed in Germany.

The results confirm the role of burnout as a mediator between psychosocial working conditions and symptoms of depression. An increase in burnout was associated with a deterioration in the psychological as well as physical dimension of the ability to work, while symptoms of depression were only associated with the psychological dimension of the ability to work. No consistent interactions with cognitive performance were discovered. The only striking aspect was the connection between reduced response times and a higher incidence of burnout.

Older nurses exhibited a lower incidence of burnout and symptoms of depression; in addition, the influence of burnout on the ability to work was stronger among older employees. The results support the assumption of a domain of burnout which is independent of any symptoms of depression and potentially associated with limitations in the ability to work and cognitive performance.

Sub-project 3: Depression, work-related factors and the processing of information in the central nervous system (Leibniz Research Centre for Working Environment and Human Factors).

The study investigated the extent to which employed persons in occupations involving increased emotional stress who suffer from symptoms of depression or burnout differ from employed persons who do not have such symptoms in terms of psychosocial work-related stress, individual-related factors, the ability to work, cognitive performance and functional brain activity. The latter was examined with the support of event-correlated potentials (ECP) which can be extracted from an electroencephalogram (EEG).

Employed persons with symptoms of burnout or depression reported a reduced ability to work, a significantly weaker internal as well as stronger external locus of control, a lower balance of emotions and more psychosocial work-related stress than those without such symptoms. In the cognitive tests, with the exception of one particularly difficult task, there were no differences in performance between those who did or did not have such symptoms.

In the ECP, in comparison with employed persons without such symptoms, employed persons suffering from symptoms of depression demonstrated an acceleration of error handling and a slowdown of stimulus processing. Employed persons with symptoms of burnout demonstrated a weakening of their task preparation, an early error detection and delayed processing of negative feedback. Following target stimuli, the early stimulus processing was enhanced and subsequent cognitive functions were slightly impaired. The ECP results reveal both cognitive deficits and compensatory mechanisms in employed persons suffering from burnout which are not (yet) apparent in their behaviour.

The available findings can help to improve the diagnosis of symptoms of depression or burnout with the support of sophisticated performance tests and EEG-based methods.