title: Axis II comorbidity in euthymic bipolar disorder patients: no differences between bipolar I and II subtypes.
abstract: BACKGROUND
  Bipolar disorder type II (BDII) has been considered since its distinction from bipolar disorder type I (BDI) as a milder form, on the basis of cross-sectional symptoms intensity. Longitudinal data, on the contrary, do suggest that it is at least as severe as BDI, if not even more chronic and impairing. Few studies investigated differences in Axis II comorbidity in bipolar disorder patients according to bipolar subtypes, and none examined patients during prolonged euthymia. The aim of the study was to determine comorbidity rates for personality disorders in euthymic bipolar subjects, comparing bipolar type I and II disorders (BDI and BDII).
  
  
  METHODS
  186 DSM-IV (SCID-I) bipolar disorder subjects were enrolled; all patients were euthymic for at least two months, as confirmed by a HAM-D<8 and a YMRS<6. Axis II comorbidity was evaluated through SCID-II. Differences in Axis II comorbidity rates were examined with the Pearson's Chi-square test.
  
  
  RESULTS
  Of the subjects included, 71 had BDI and 115 BDII. At least a personality disorder was present in 42.5% of all bipolars, 43.7% of BDI and 41.7% of BDII. No differences were detected between the two subgroups for any single personality disorder.
  
  
  CONCLUSIONS
  We relied only on the patients' reports in assessing personality disorders; the sample was made of subjects referred to a tertiary centre who were able to maintain euthymia.
  
  
  CONCLUSIONS
  Our study confirms the high comorbidity rates for personality disorders in bipolar subjects and provides evidence that BDII, with regard to Axis II comorbidity, is as severe as BDI.
authors.affiliation: Department of Neurosciences, Mood and Anxiety Disorders Unit, University of Turin, Via Cherasco 11-10126 Torino, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Rosso
authors.forename: Umberto
authors.initials: U
authors.lastname: Albert
authors.forename: Filippo
authors.initials: F
authors.lastname: Bogetto
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Maina
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000145:classification / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D015897:Comorbidity; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008297:Male; D008875:Middle Aged; D010554:Personality Disorders / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology