title: A prospective latent analysis study of Axis I psychiatric co-morbidity of DSM-IV major depressive disorder.
abstract: BACKGROUND
  We tested the degree to which longitudinal observations fit two hypotheses of psychiatric co-morbidity in DSM-IV major depressive disorder (MDD) among adult patients: (1) Axis I co-morbidity is dependent on major depressive episode (MDE) course, and (2) Axis I co-morbidity is independent of MDE course.
  
  
  METHODS
  In the Vantaa Depression Study (VDS), 269 psychiatric secondary-care patients with a DSM-IV MDD were evaluated with the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) at intake and at 6 and 18 months. Three evaluations of co-morbidity were available for 193 out of 259 living patients (75%). A latent curve model (LCM) was used to examine individual-level changes in depressive and anxiety symptoms across time. Outcome of MDD was modeled in terms of categorical DSM-IV diagnosis and Beck Depression Inventory (BDI) and Hamilton Depression Rating Scale (HAMD) scores, and co-morbidity in terms of categorical DSM-IV anxiety and alcohol use disorder (AUD) diagnoses and Beck Anxiety Inventory (BAI) scores.
  
  
  RESULTS
  Depression and anxiety correlated cross-sectionally at baseline. Longitudinally, changes in depression and anxiety correlated in both the 0-6 and 6-18 months time windows. Higher baseline depression raised the likelihood of an AUD at 6 months, and patients with more depressive symptoms in the 0-6 months time window were more likely to have had an AUD at 6 months, which further linked to less improvement in depression symptoms in the 6-18 months time window.
  
  
  CONCLUSIONS
  Longitudinal and individual-level courses of both internalizing and externalizing disorders in adult patients with MDD seem to be dependent, albeit to differing degrees, on the course of depressive symptoms.
authors.affiliation: Mood, Depression and Suicidal Behavior Unit, Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Melartin
authors.affiliation: Mood, Depression and Suicidal Behavior Unit, Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: O
authors.initials: O
authors.lastname: Mantere
authors.affiliation: Operations and Technology Department, IE Business School, Madrid, Spain.
authors.forename: M
authors.initials: M
authors.lastname: Ketokivi
authors.affiliation: Mood, Depression and Suicidal Behavior Unit, Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: E
authors.initials: E
authors.lastname: Isometsä
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000453:epidemiology*; D001008:Anxiety Disorders / Q000453:epidemiology*; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000453:epidemiology*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies