This prospective longitudinal study examined the effect of two work conditions (work demands and decision latitude) and their interaction on five measures of mental illness: depressive, anxiety, and alcohol abuse disorder, as well as depressive and anxiety symptoms. Additionally, the extent to which any of these relationships were due to youth with prior mental health problems being selected or selecting stressful job conditions. Participants included 604 working young adults (M age: 22), a subsample of a randomly selected sample in a community-based longitudinal study. Information on family environment, youth characteristics, and mental illness were gathered prospectively during interviews in 1983, 1985-1986, and 1992. Youths who were working in 1992 or in the previous year were asked questions about the two work conditions. Relationships between work conditions and mental illness were modeled using hierarchical linear and logistic regression as well as structural equation modeling and two stage least squares analyses. Results indicated that young adult alcohol abuse disorder was predicted from the interaction between work demands and decision latitude with control for prior alcohol abuse, gender, age, race, parental socioeconomic status, educational status, full-time and part-time work, work instability (fired or laid off in past 5 years) and either concurrent disorders (i.e. anxiety and depressive disorders) or social support. Another consistent finding was that low decision latitude was associated with anxiety abuse disorder among young adult workers. Finally, high work demands and low decision latitude were additively associated with depressive symptoms after control for prior depressive symptoms, work status and demographic variables. A weak interaction effect was found between decision latitude, work demands and depressive disorder, along with a selection effect of youth with depressive disorder being more likely to work in jobs with high demands and low decision latitude during young adulthood. No strong associations were found between the work conditions, social support and anxiety symptoms. A fairly extensive literature has accumulated on Karasek's demand-control model with regard to a range of mental and physical health outcomes (Vander Doef & Maes, 1999). In general, at least one work condition predicts the outcome supporting the theory that the difficult work conditions specified by Karasek may negatively affect mental health. However, as in this study there are many inconsistencies. Further investigation is needed into the effects of stressful work conditions. Qualitative investigation with young adult workers that examined the different domains of work demands and decision latitude may provide information that can be used to further hone the model. In addition to working to better determine what is being measured by the demand-decision latitude model, there are other stressful work conditions that may negatively affect young workers and need investigating, such as role ambiguity, poor organizational climate, and ineffective supervisors.
Department of Sociomedical Sciences, Columbia University, 600 West 168th 4th Floor, New York, NY 10032