title: Psychological distress and risk of long-term disability: population-based longitudinal study.
abstract: BACKGROUND
  Common mental disorders are known to cause long-term disability, although not much is known about long-term consequences of milder forms of psychological distress.
  
  
  OBJECTIVE
  To investigate the association between increasing levels of psychological distress and 5-year risk of long-term disability pensions awarded for somatic or psychiatric conditions.
  
  
  METHODS
  In this longitudinal population-based study, a cohort of 17,205 individuals, aged 18-64 years, recruited in 2002 in Stockholm County was prospectively followed up for new disability pension awards. The 12-item General Health Questionnaire (GHQ-12) was used to measure baseline psychological distress, and participants were categorised as having no, mild, moderate or severe psychological distress (GHQ-12 scores of 0; 1-2; 3-7 and 8-12, respectively). Details of new disability pension awards were obtained through record linkage with the Swedish National Insurance register. Comprehensive information on a range of sociodemographic, lifestyle and health characteristics was available.
  
  
  RESULTS
  Increasing levels of psychological distress at baseline were associated with an increased likelihood of obtaining a disability pension later in life. Even mild psychological distress was independently associated with the award of a disability pension for both somatic (HR=1.7; 95% CI 1.3 to 2.2) and psychiatric diagnoses (2.2; 1.4 to 3.6). Over a quarter of disability pensions awarded for a somatic diagnosis, and almost two-thirds awarded for a psychiatric diagnosis, could be attributed to psychological distress.
  
  
  CONCLUSIONS
  Mild psychological distress may be associated with more long-term disability than previously acknowledged and its public health importance may be underestimated.
authors.affiliation: Academic Unit of Psychiatry, School of Social and Community Medicine, University of Bristol, Oakfield House, Oakfield Grove, Clifton, Bristol BS8 2BN, UK. dheeraj.rai@bristol.ac.uk
authors.forename: Dheeraj
authors.initials: D
authors.lastname: Rai
authors.forename: Kyriaki
authors.initials: K
authors.lastname: Kosidou
authors.forename: Michael
authors.initials: M
authors.lastname: Lundberg
authors.forename: Ricardo
authors.initials: R
authors.lastname: Araya
authors.forename: Glyn
authors.initials: G
authors.lastname: Lewis
authors.forename: Cecilia
authors.initials: C
authors.lastname: Magnusson
mesh_terms: D000293:Adolescent; D000328:Adult; D006233:Persons with Disabilities; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D001523:Mental Disorders / Q000175:diagnosis; D008875:Middle Aged; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods; D012923:Social Class; D013315:Stress, Psychological / Q000150:complications*; D011795:Surveys and Questionnaires; D013548:Sweden; D055815:Young Adult