title: Depression in bipolar disorder versus major depressive disorder: results from the National Epidemiologic Survey on Alcohol and Related Conditions.
abstract: OBJECTIVE
  To compare the clinical features and course of major depressive episodes (MDEs) occurring in subjects with bipolar I disorder (BD-I), bipolar II disorder (BD-II), and major depressive disorder (MDD).
  
  
  METHODS
  Data were drawn from the National Epidemiologic Survey on Alcohol and Related Conditions (2001-2002), a nationally representative face-to-face survey of more than 43000 adults in the USA, including 5695 subjects with lifetime MDD, 935 with BD-I and lifetime MDE, and 494 with BD-II and lifetime MDE. Differences on sociodemographic characteristics and clinical features, course, and treatment patterns of MDE were analyzed.
  
  
  RESULTS
  Most depressive symptoms, family psychiatric history, anxiety disorders, alcohol and drug use disorders, and personality disorders were more frequent-and number of depressive symptoms per MDE was higher-among subjects with BD-I, followed by BD-II, and MDD. BD-I individuals experienced a higher number of lifetime MDEs, had a poorer quality of life, and received significantly more treatment for MDE than BD-II and MDD subjects. Individuals with BD-I and BD-II experienced their first mood episode about ten years earlier than those with MDD (21.2, 20.5, and 30.4 years, respectively).
  
  
  CONCLUSIONS
  Our results support the existence of a spectrum of severity of MDE, with highest severity for BD-I, followed by BD-II and MDD, suggesting the utility of dimensional assessments in current categorical classifications.
authors.affiliation: Child and Adolescent Psychiatry Department, Hospital General Universitario Gregorio Marañón, Centro de Investigación Biomédica en Red de Salud Mental, CIBERSAM, Madrid, Spain. cmoreno@hggm.es
authors.forename: Carmen
authors.initials: C
authors.lastname: Moreno
authors.forename: Deborah S
authors.initials: DS
authors.lastname: Hasin
authors.forename: Celso
authors.initials: C
authors.lastname: Arango
authors.forename: Maria A
authors.initials: MA
authors.lastname: Oquendo
authors.forename: Eduard
authors.initials: E
authors.lastname: Vieta
authors.forename: Shangmin
authors.initials: S
authors.lastname: Liu
authors.forename: Bridget F
authors.initials: BF
authors.lastname: Grant
authors.forename: Carlos
authors.initials: C
authors.lastname: Blanco
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000437:Alcoholism / Q000150:complications* / Q000453:epidemiology*; D001714:Bipolar Disorder / Q000145:classification / Q000453:epidemiology*; D003863:Depression / Q000453:epidemiology*; D003865:Major Depressive Disorder / Q000453:epidemiology*; D005006:Ethnicity; D005260:Female; D006306:Health Surveys; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D008875:Middle Aged; D011336:Probability; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D012737:Sex Factors; D014481:United States / Q000453:epidemiology; D055815:Young Adult