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NZ Study: Rising Rates of Depression and Work Stress

 

In the United States and the European Union, 30–40% of workers are exposed to work stress, and these rates appear to have increased since the 1990s (National Institute of Occupational Health and Safety, 1999; European Foundation for the Improvement of Living and Working Conditions, 2005). Stressful work conditions predict poor mental health and there is growing concern that such conditions contribute to the population burden of psychiatric illness. Yet, past research is limited by several methodological shortcomings, which a New Zealand study (2006) aimed to address using data from a birth cohort followed from childhood to adulthood in almost 900 study participants over a 32 year period.

 Rates of depression have been rising globally significantly, as well as rates of work stress. The influence of work stress on diagnosed depression and anxiety in young working adults was tested in a 891 participant study enrolled in the Dunedin study (“Work stress precipitates depression and anxiety in young, working women and men”) with an average age of 32 years. Study members (52% male) were born in Dunedin, New Zealand, between April 1972– March 1973 and participated in their first follow-up assessment at age 3. The study represents the full range of socio-economic status (predominantly white) in the general population of New Zealand’s South Island.  Assessments have been carried out at ages 3, 5, 7, 9, 11, 13, 15, 18, 21, 26 and 32.  
 
Work stress (including psychological job demands, work decisions, low work social support and physical work demands) was ascertained by interview. Major depression and generalised anxiety disorder were ascertained using the Diagnostic Interview Schedule and diagnosed according to DSM-IV criteria.
 
Results
Participants exposed to high psychological job demands (high stress environments, excessive workload, extreme time pressures) had a two-fold risk of major depression or generalised anxiety disorder compared to those with low job demands. Analyses ruled out the possibility that the association between work stress and disorder resulted from study members’ socio-economic position, a personality tendency to report negatively, or a history of psychiatric disorder prior to labor-market entry. High-demand jobs were associated with the onset of new depression and anxiety disorder in individuals without any pre-job history of diagnosis or treatment for either disorder.
 
Conclusions
High work stress appears to precipitate diagnosable depression, and induces a state of stress and anxiety in previously-healthy young workers. Helping workers cope with work stress or reducing work stress levels could prevent the occurrence of clinically-significant depression and anxiety. In a birth cohort of 32-year old working women and men, we found a graded relationship between psychological job demands and the risk of depression or anxiety; in study members exposed to high psychological job demands the risk was two times higher than in those with low demands. The combination of multiple work stressors conferred an even higher risk, especially in men. Through our long term study we found that psychological job demands contribute to an increased risk of two common psychiatric disorders: major depression and generalised anxiety disorder. Hence, work stress is associated with psychiatric outcomes of clinical significance that bear great healthcare and societal costs.
In addition, job demands that exceed the individual’s coping abilities are perceived as stressful and could influence the risk of psychiatric disorder through biological, psychological, psychosomatic and behavioural mechanisms. As suggested by animal and human studies, biological mechanisms could involve the dysregulation of stress hormones such as adrenalin and cortisol. Persistently elevated stress hormone levels may have direct neuro-toxic effects on the brain, and can induce down-regulation of the glucocorticoid receptor, which can potentially cause multiple systemic dysregulation.
 Coping mechanisms include feelings of helplessness, which may result from individuals’ perceived inability to influence their condition. In addition, work stress may lead to symptoms of fatigue, difficulty sleeping, poor concentration, and distress.  Finally, behavioural mechanisms linking work stress to poor mental health might include an inability to engage in leisure activities and to maintain strong social networks.
We found that very high psychological job demands were uniquely associated with mental disorders, suggesting that job demands influence the occurrence of depression and anxiety rather than vice versa.
A key strength of our study is that study members were 32 years old when work characteristics and depression and anxiety were fully assessed. This is an age when individuals settle into their professional careers and are less likely to have selected out of stressful jobs than older workers (on average, Dunedin study members were employed in their current occupation for one and a half years). It is also a period of elevated risk for psychiatric disorders. Thus, our results suggest that work stress may precipitate common mental disorders, which are a major cause of morbidity, poor quality of life, as well as social impairment and lost work productivity (World Health Organisation, 2001), setting in motion a cycle from work demands to mental disorders to lost work productivity.
As shown by worksite intervention trials that increase workers’ ability to manage their workload, institutional-level decreases in work demands could help reduce rates of depression and anxiety in the working population though changes may be difficult to implement. At the individual level, effective coping skills and relaxation techniques help workers better manage work stress and reduce the risk of psychiatric disorder. In our study of young workers, 45% of new cases of depression and anxiety were attributable to work stress, suggesting that young adulthood is an especially propitious life stage for preventing new cases of common mental disorders.
 Recent trends indicate that prevalence rates of depression and anxiety are increasing, but causes of this historical change are not well understood. . Simultaneously, rates of work stress have also been rising (European Foundation for the Improvement of Living and Working Conditions, 2005; National Institute of Occupational Health and Safety, 1999), and deteriorating work conditions could contribute to an increased risk of mental disorders at the individual as well as the societal level.
Supported by the U.S. National Institute of Mental Health, the U.K. Medical Research Council and the U.K. Economic and Social Research Council, the William T. Grant Foundation, the Health Research Council of New Zealand, and the Statistics and Research Division of France’s Ministry of Health and Social Affairs. T.E.M. and A.C. are Royal Society Wolfson Research Merit Award holders. We thank the Dunedin study members, Unit research staff, study founder Phil Silva, PhD, and Rhiannon Newcombe.

 

References

  • American Psychiatric Association. Diagnostic and statistical manual of mental disorders. 4. American Psychiatric Association; Washington, DC: 1994.
  • Avitsur R, Stark JL, Sheridan JF. Social stress induces glucocorticoid resistance in subordinate animals. Hormones and Behavior. 2001;39(4):247–257. [PubMed]
  • Davis P, Jenkin G, Coope P. New Zealand Socio-economic Index 1996. Wellington, New Zealand: Statistics New Zealand; 2003.
  • de Kloet ER, Joëls M, Holsboer F. Stress and the brain: From adaptation to disease. Nature Reviews Neuroscience. 2005;6:463–475.
  • European Foundation for the Improvement of Living and Working Conditions. Fourth European Working Survey. [Accessed December 13, 2006]. http://www.eurofound.eu.int/pubdocs/2006/78/en/1/ef0678en.pdf.
  • Karasek R, Theorell T. Healthy Work: stress, productivity and the reconstruction of working life. Basic Books; New York, NY: 1990.
  • Krueger RF, Caspi A, Moffitt TE, Silva PA. The structure and stability of common mental disorders (DSM III-R): a longitudinal-epidemiological study. Journal of Abnormal Psychology. 1998;107(2):216–227. [PubMed]
  • McEwen BS. Protective and damaging effects of stress mediators: allostatis and allostatic load. New England Journal of Medicine. 1998;338:171–179. [PubMed] 
  • Mineka S, Watson D, Clark LA. Comorbidity of anxiety and unipolar mood disorders. Annual Review of Psychology. 1998;49:377–412.
  • Mino Y, Babazono A, Tsuda T, Yasuda N. Can stress management at the workplace prevent depression? A randomized controlled trial. Psychotherapy and Psychosomatics. 2006;75(3):177–182. [PubMed]
  • Pariante CM, Miller AH. Glucocorticoid receptors in major depression: relevance to pathophysiology and treatment. Biological Psychiatry. 2001;49(5):391–404. [PubMed]
  • Parkes KR. Coping, negative affectivity, and the work environment: additive and interactive predictors of mental health. Journal of Applied Psychology. 1990;75(4):399–409. [PubMed]
  • Paterniti S, Niedhammer I, Lang T, Consoli SM. Psychosocial factors at work, personality traits and depressive symptoms. Longitudinal results from the GAZEL Study. British Journal of Psychiatry. 2002;181:111–117. [PubMed]
  • Sapolsky RM, Krey LC, McEwen BS. The neuroendocrinology of stress and aging: the glucocorticoid cascade hypothesis. Endocrine Reviews. 1986;7(3):284–301. [PubMed]
  • Schwarzer R. Stress and coping from a social-cognitive perspective. Annals of the New York Academy of Sciences. 1998;30(851):531–537. [PubMed]
  • Shields M. Long working hours and health. Health Reports. 1999;11(2):33–48. [PubMed]
  • Statistics New Zealand. New Zealand standard classification of occupations. Statistics New Zealand; Wellington, New Zealand: 1999.
  • Tennant C. Work-related stress and depressive disorders. Journal of Psychosomatic Research. 2001;51:697–704. [PubMed]
  • Twenge JM. The age of anxiety? Birth cohort changes in anxiety and neuroticism, 1952–1993. Journal of Personality and Social Psychology. 2000;79(6):1007–1021. [PubMed]
  • World Health Organization. World health report 2001-mental health: new understanding, new hope. [Accessed December 13, 2006]. http://www.who.int/whr/2001/en/

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