Job Strain and Psychologic Distress Influence on Sickness Absence Among Finnish Employees Marianna Virtanen, PhD, Jussi Vahtera, MD, PhD, Jaana Pentti, MSc, Teija Honkonen, MD, PhD, Marko Elovainio, PhD, Mika Kivimäki, PhD Background: Work stress is a recognized risk factor for mental health disorders, but it is not known whether work stress is associated with the morbidity among individuals with psychologic distress. Another shortcoming in earlier research is related to common method bias—the use of individual perceptions of both work stress and psychologic distress. This prospective study was assessed using the General Health Questionnaire (GHQ-12), which identified psychologic distress as a predictor of sickness absence and the effect of work-unit measures of job strain on sickness absence among cases. Methods: Survey data were collected on work stress, indicated by high job strain, for a cohort of public sector employees (6663 women, 1323 men), aged 18 to 62 at baseline in 2000 –2002, identified as GHQ-12 cases. Coworker assessments of job strain were used to control for bias due to response style. A 2-year follow-up included recorded long-term (7 days) medically certified sickness absence. Adjustments were made for age, socioeconomic position, baseline chronic physical disease, smoking, and heavy alcohol consumption. Results: Cases with psychologic distress had 1.3 to 1.4 times higher incidence of long-term sickness absence than noncases. Among cases, high job strain predicted sickness absence (hazard ratio 1.17 in women, 1.41 in men). The significant effect of job strain on sickness absence was found among workers in high socioeconomic positions (hazard ratio 1.54 for women, 1.58 for men) but not among employees in low socioeconomic positions (hazard ratio 1.06 for women, 1.31 for men). Conclusions: Psychologic distress has an independent effect on medically certified sickness absence. The identification of employees with high job strain and the improvement of their working conditions should be considered as an important target in the prevention of adverse consequences of psychologic distress. (Am J Prev Med 2007;33(3):182–187) © 2007 American Journal of Preventive Medicine Introduction O ver the past decade, data from surveys and registers have shown increasing psychologic stress at work, and that mental disorders, espe- cially depression, are a growing reason for work disabil- ity and premature exclusion from the labor market. 1–4 Although severe mental disorders predict functional incapacity and work disability, there is a lack of evi- dence on whether the widely used General Health Questionnaire (GHQ) 5 may also be useful in screening for mental disorders that can increase work disability risk in the form of long-term sickness absence. 6,7 To most effectively prevent work disability and pre- mature exclusion from the labor market, one should take into account not only factors that affect the risk in healthy populations but also those influencing the prognosis of workers with psychologic distress. One of the most widely used work stress theories is the job strain model, 8,9 also known as the demand-control model. According to the model, high job demands, low job control and, in particular, a combination of high job demands and low job control, referred to as job strain, involves a health risk. Extensive literature has shown psychosocial work stress to be among the risk factors for mental ill health and sickness absence in working populations. 8 –17 Furthermore, one study has shown that low job control plays a more important role in mental distress among individuals in high socioeco- nomic positions (SEPs) than among those in low SEPs. 18 From the Finnish Institute of Occupational Health, Topeliuksenkatu, Helsinki, Finland (Virtanen, Vahtera, Pentti, Honkonen, Kivimäki); the National Research and Development Centre for Health and Welfare (Elovainio), Helsinki, Finland; and the International Centre for Health and Society, Department of Epidemiology and Public Health (Kivimäki), University College London Medical School, Lon- don, UK Address correspondence and reprint requests to: Marianna Virtanen, PhD, Finnish Institute of Occupational Health, Topeliuksenkatu 41 a A, FIN-00250 Helsinki, Finland. E-mail: marianna.virtanen@ ttl.fi. 182 Am J Prev Med 2007;33(3) 0749-3797/07/$–see front matter © 2007 American Journal of Preventive Medicine • Published by Elsevier Inc. doi:10.1016/j.amepre.2007.05.003