title: Bipolar mixed episodes and antidepressants: a cohort study of bipolar I disorder patients.
abstract: OBJECTIVE
  The aim of this study was to elucidate the factors associated with the occurrence of mixed episodes, characterized by the presence of concomitant symptoms of both affective poles, during the course of illness in bipolar I disorder patients treated with an antidepressant, as well as the role of antidepressants in the course and outcome of the disorder.
  
  
  METHODS
  We enrolled a sample of 144 patients followed for up to 20 years in the referral Barcelona Bipolar Disorder Program and compared subjects who had experienced at least one mixed episode during the follow-up (n=60) with subjects who had never experienced a mixed episode (n=84) regarding clinical variables.
  
  
  RESULTS
  Nearly 40% of bipolar I disorder patients treated with antidepressants experienced at least one mixed episode during the course of their illness; no gender differences were found between two groups. Several differences regarding clinical variables were found between the two groups, but after performing logistic regression analysis, only suicide attempts (p<0.001), the use of serotonin norepinephrine reuptake inhibitors (p=0.041), switch rates (p=0.010), and years spent ill (p=0.022) were significantly associated with the occurrence of at least one mixed episode during follow-up.
  
  
  CONCLUSIONS
  The occurrence of mixed episodes is associated with a tendency to chronicity, with a poorer outcome, a higher number of depressive episodes, and greater use of antidepressants, especially serotonin norepinephrine reuptake inhibitors.
authors: Bipolar Disorders Program, Clinical Institute of Neuroscience, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Marc
authors: M
authors: Valentí
authors: Isabella
authors: I
authors: Pacchiarotti
authors: Adriane R
authors: AR
authors: Rosa
authors: C Mar
authors: CM
authors: Bonnín
authors: Dina
authors: D
authors: Popovic
authors: Alessandra M A
authors: AM
authors: Nivoli
authors: Andrea
authors: A
authors: Murru
authors: Iria
authors: I
authors: Grande
authors: Francesc
authors: F
authors: Colom
authors: Eduard
authors: E
authors: Vieta
mesh_terms: D000293:Adolescent; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000145:classification / Q000188:drug therapy*; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D011569:Psychiatric Status Rating Scales; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000928:Antidepressive Agents