title: Mood episodes and mood disorders: patterns of incidence and conversion in the first three decades of life.
abstract: OBJECTIVE
  Significant questions remain regarding both the incidence patterns of mood episodes in adolescents and young adults from the community and the conversion rate from unipolar to bipolar disorders. We addressed these issues by examining data from a prospective longitudinal community study to (i) determine the cumulative incidence of mood episodes and disorders in the first three decades of life; (ii) determine the risk for first onset of depression among individuals with a previous history of hypomanic/manic episodes and vice versa; and (iii) determine the clinical and treatment characteristics of these subjects.
  
  
  METHODS
  Using the Munich-Composite International Diagnostic Interview, clinically trained interviewers assessed mood episodes and mental disorders in 3,021 community subjects (aged 14-24 at baseline and 21-34 at third follow-up).
  
  
  RESULTS
  The estimated cumulative incidence at age 33 was 2.9% for manic, 4.0% for hypomanic, 29.4% for major depressive, and 19.0% for minor depressive episodes; overall, 26.0% had unipolar major depression, 4.0% bipolar depression, 1.5% unipolar mania, and 3.6% unipolar hypomania (no major depression). Overall, 0.6% and 1.8% had unipolar mania or hypomania, respectively, without indication for even minor depression. A total of 3.6% of the initial unipolar major depression cases subsequently developed (hypo)mania, with particularly high rates in adolescent onset depression (< 17 years: 9%). A total of 49.6% of the initial unipolar mania cases subsequently developed major depression and 75.6% major or minor depression. While bipolar cases had more adverse clinical and course depression characteristics and higher treatment rates than unipolar depressed cases, bipolar cases did not significantly differ in mania characteristics from unipolar mania cases.
  
  
  CONCLUSIONS
  Unipolar and bipolar mood disorders are more frequent than previously thought in adolescence and young adulthood, a time period when both the recognition and the intervention rates by the healthcare system are rather low. 'Conversion' to bipolar disorder is limited in initial unipolar depression, but common in initial unipolar mania. The remaining unipolar mania cases appear to be significant in terms of clinical and course characteristics and thus require more research attention to replicate these findings.
authors.affiliation: Institute of Clinical Psychology and Psychotherapy, Technische Universitaet Dresden, 01187 Dresden, Germany. beesdo@psychologie.tu-dresden.de
authors.forename: Katja
authors.initials: K
authors.lastname: Beesdo
authors.forename: Michael
authors.initials: M
authors.lastname: Höfler
authors.forename: Ellen
authors.initials: E
authors.lastname: Leibenluft
authors.forename: Roselind
authors.initials: R
authors.lastname: Lieb
authors.forename: Michael
authors.initials: M
authors.lastname: Bauer
authors.forename: Andrea
authors.initials: A
authors.lastname: Pfennig
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology; D003866:Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology; D003937:Diagnosis, Differential; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D019964:Mood Disorders / Q000145:classification / Q000175:diagnosis* / Q000453:epidemiology*; D011379:Prognosis; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D055815:Young Adult
references.citation: Arch Gen Psychiatry. 2007 May;64(5):543-52
references.pmid: 17485606
references.citation: Psychol Med. 1997 Sep;27(5):1079-89
references.pmid: 9300513
references.citation: Soc Psychiatry Psychiatr Epidemiol. 1998 Dec;33(12):587-95
references.pmid: 9857791
references.citation: Acta Psychiatr Scand Suppl. 2004;(420):21-7
references.pmid: 15128384
references.citation: J Abnorm Psychol. 1998 Feb;107(1):128-40
references.pmid: 9505045
references.citation: J Abnorm Psychol. 1993 Feb;102(1):133-44
references.pmid: 8436689
references.citation: J Am Acad Child Adolesc Psychiatry. 1995 Jun;34(6):754-63
references.pmid: 7608049
references.citation: Int J Neuropsychopharmacol. 2003 Jun;6(2):145-54
references.pmid: 12890308
references.citation: Soc Psychiatry Psychiatr Epidemiol. 1998 Nov;33(11):568-78
references.pmid: 9803825
references.citation: Biol Psychiatry. 2006 Nov 1;60(9):991-7
references.pmid: 17056393
references.citation: Prog Neuropsychopharmacol Biol Psychiatry. 2009 Feb 1;33(1):86-93
references.pmid: 18992784
references.citation: Depress Anxiety. 1998;7(1):3-14
references.pmid: 9592628
references.citation: J Psychiatr Res. 1994 Jan-Feb;28(1):57-84
references.pmid: 8064641
references.citation: J Am Acad Child Adolesc Psychiatry. 1995 Apr;34(4):454-63
references.pmid: 7751259
references.citation: World Psychiatry. 2007 Oct;6(3):168-76
references.pmid: 18188442
references.citation: Am J Psychiatry. 2003 Nov;160(11):2049-51
references.pmid: 14594755
references.citation: Clin Psychol Rev. 2005 May;25(3):307-39
references.pmid: 15792852
references.citation: Eur Addict Res. 2000 Dec;6(4):170-82
references.pmid: 11124570
references.citation: Psychother Psychosom. 2008;77(6):384-9
references.pmid: 18716424
references.citation: Soc Psychiatry Psychiatr Epidemiol. 2002 Aug;37(8):372-9
references.pmid: 12195544
references.citation: Eur Neuropsychopharmacol. 2008 Jul;18(7):535-49
references.pmid: 18501566
references.citation: J Affect Disord. 2005 Feb;84(2-3):149-57
references.pmid: 15708412
references.citation: Arch Gen Psychiatry. 2005 Jun;62(6):593-602
references.pmid: 15939837
references.citation: J Affect Disord. 1998 Sep;50(2-3):143-51
references.pmid: 9858074
references.citation: Am J Psychiatry. 2006 Feb;163(2):225-31
references.pmid: 16449475
references.citation: J Clin Psychiatry. 2002 Feb;63(2):120-5
references.pmid: 11874212
references.citation: Psychol Med. 1998 Jan;28(1):109-26
references.pmid: 9483687
references.citation: Bipolar Disord. 2000 Sep;2(3 Pt 2):281-93
references.pmid: 11249806
references.citation: Child Adolesc Psychiatr Clin N Am. 2002 Jul;11(3):461-75, vii
references.pmid: 12222078
references.citation: J Affect Disord. 2003 Jan;73(1-2):133-46
references.pmid: 12507746
references.citation: J Affect Disord. 1979 Mar;1(1):59-68
references.pmid: 162182
references.citation: J Affect Disord. 2002 Apr;68(2-3):203-13
references.pmid: 12063148
references.citation: Eur Addict Res. 1998 Mar;4(1-2):18-27
references.pmid: 9740814