title: Do unexplained symptoms predict anxiety or depression? Ten-year data from a practice-based research network.
abstract: BACKGROUND
  Unexplained symptoms are associated with depression and anxiety. This association is largely based on cross-sectional research of symptoms experienced by patients but not of symptoms presented to the GP.
  
  
  OBJECTIVE
  To investigate whether unexplained symptoms as presented to the GP predict mental disorders.
  
  
  METHODS
  Cross-sectional and longitudinal analysis of data from a practice-based research network of GPs, the Transition Project, in the Netherlands.
  
  
  METHODS
  All data about contacts between patients (n = 16,000) and GPs (n = 10) from 1997 to 2008 were used. The relation between unexplained symptoms episodes and depression and anxiety was calculated and compared with the relation between somatic symptoms episodes and depression and anxiety. The predictive value of unexplained symptoms episodes for depression and anxiety was determined.
  
  
  RESULTS
  All somatoform symptom episodes and most somatic symptom episodes are significantly associated with depression and anxiety. Presenting two or more symptoms episodes gives a five-fold increase of the risk of anxiety or depression. The positive predictive value of all symptom episodes for anxiety and depression was very limited. There was little difference between somatoform and somatic symptom episodes with respect to the prediction of anxiety or depression.
  
  
  CONCLUSIONS
  Somatoform symptom episodes have a statistically significant relation with anxiety and depression. The same was true for somatic symptom episodes. Despite the significant odds ratios, the predictive value of symptom episodes for anxiety and depression is low. Consequently, screening for these mental health problems in patients presenting unexplained symptom episodes is not justified in primary care.
authors.affiliation: Department of Primary and Community Care, Radboud University Nijmegen Medical Centre, The Netherlands.
authors.forename: Kees
authors.initials: K
authors.lastname: van Boven
authors.forename: Peter
authors.initials: P
authors.lastname: Lucassen
authors.forename: Hiske
authors.initials: H
authors.lastname: van Ravesteijn
authors.forename: Tim
authors.initials: T
authors.lastname: olde Hartman
authors.forename: Hans
authors.initials: H
authors.lastname: Bor
authors.forename: Evelyn
authors.initials: E
authors.lastname: van Weel-Baumgarten
authors.forename: Chris
authors.initials: C
authors.lastname: van Weel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001008:Anxiety Disorders / Q000175:diagnosis / Q000209:etiology*; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000175:diagnosis / Q000209:etiology*; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D013001:Somatoform Disorders / Q000523:psychology*; D055815:Young Adult