Long-term sickness absence for psychiatric disorder : the association with staff downsizing, treatment, workplace-oriented rehabilitation, and subsequent cause-specific inpatient care and mortality

Psychiatric disorders have increased as causes of long-term sickness absence in Sweden as well as in other countries. Still, there is limited research on psychiatric sickness absence. The overall objective of this thesis was to contribute to the knowledge of long-term sickness absence for psychiatric disorders, focusing on the associations with staff downsizing, treatment, workplace-oriented rehabilitation, and also subsequent inpatient care and mortality.

In study I, aggregated data on psychiatric long-term sickness absence from AFA Insurance and information on staff numbers from the Swedish Association of Local Authorities and Regions was used. Seventeen county councils were examined. The results showed that staff downsizing was associated with subsequent increases in long-term sickness absence for psychiatric disorders. That is, the greater the staff reduction, the larger was the increase in psychiatric long-term sickness absence. The associations were similar in men and women as well as in different age groups, although statistical significance was only reached in the groups of women and middle-aged employees.

Study II was based on employees (80% from the Swedish municipalities and county councils), initially long-term sick-listed for a psychiatric disorder who answered a questionnaire on, e.g., received treatment/rehabilitation. This information was linked to outcome data on sick leave. The results showed that those who reported having received workplace-oriented rehabilitation had reduced odds of subsequent sickness absence compared with those who did not. Drug treatment and physiotherapy, respectively, increased the odds of later sickness absence and disability pension.

In study III-IV, employees (in November/year) within municipalities and county councils were examined. Register linkages was done between data on socio-demographic factors, sickness absence, inpatient care and mortality. The analyses revealed that psychiatric long-term sickness absence was associated with increased risk of subsequent cause-specific inpatient care and mortality.

In summary, one finding of this thesis was that staff downsizing among county council employees was associated with later increase in psychiatric long-term sickness absence. Moreover, among employees with long-term sickness absence for a psychiatric disorder, workplace-oriented rehabilitation reduced the risk of subsequent sickness absence. Finally, psychiatric long-term sickness absence was associated with increased risk of later inpatient care and death due to cardiovascular disease, cancer and suicide attempt/suicide.

List of scientific papers

I. Bryngelson A, Mittendorfer-Rutz E, Fritzell J, Åsberg M, Nygren Å. Reduction in personnel and long-term sickness absence for psychiatric disorders among employees in Swedish county councils. An ecological population-based study. Journal of occupational and environmental medicine. 2011;53(6):658-662.
https://doi.org/10.1097/JOM.0b013e31821aa706

II. Bryngelson A, Mittendorfer-Rutz E, Jensen I, Lundberg U, Åsberg M, Nygren Å. Self-reported treatment, workplace-oriented rehabilitation, change of occupation and subsequent sickness absence and disability pension among employees long-term sick-listed for psychiatric disorders: a prospective cohort study. BMJ Open. 2012;2:e001704.
https://doi.org/10.1136/bmjopen-2012-001704

III. Bryngelson A, Åsberg M, Nygren Å, Jensen I, Mittendorfer-Rutz E. Cause-specific inpatient care among employees long-term sick listed for a psychiatric disorder in Sweden 1990-2007: a prospective cohort study. [Submitted]

IV. Bryngelson A, Åsberg M, Nygren Å, Jensen I, Mittendorfer-Rutz E. All-cause and cause-specific mortality after long-term sickness absence for psychiatric disorders: a prospective cohort study. [Accepted]
https://doi.org/10.1371/journal.pone.0067887