title: Clinical features of antidepressant associated manic and hypomanic switches in bipolar disorder.
abstract: The present study investigated possible clinical differences between bipolar patients with and without manic or hypomanic switch during antidepressant (AD) treatment. The authors undertook a retrospective assessment of 169 individuals affected by bipolar disorder type I (BP I: n=96) and II (BP II: n=73) who experienced at least one manic or hypomanic episode following depression without any interposed normothymic period ("manic switch") during AD therapy. They were compared with a sex, age (+/-5 years), and ethnicity-matched group of 247 subjects, randomly selected from our pool of bipolar subjects who have never had manic switches. Only 2 of the 169 patients had had spontaneous switches before the AD-related one. Switched subjects were marginally older (t=-2.65, df=414, P=.008) compared to not switched and less frequently delusional (chi2=13.86, P=.0002). Polarity of the onset episode was more frequently depressive in switched patients (chi2=21.93, P=.00002), which had also less previous manic episodes than not switched (t=3.44, df=332, P=.0006). Those differences were more pronounced in the BP I subsample. Switched patients were more frequently BP I (chi2=29.66; P<.00001). Maintenance with mood stabilizers appears to be a strong protective factor; in fact, of the 124 individuals undertaking a mood stabilizer therapy, 21 had a switch and 103 had no switches (chi2=41.10, P<.000001). In conclusion, some clinical variables, such as the number of manic episodes, the presence of delusions, the polarity of onset episode, and the mood-stabilizing treatment, may be involved in AD-related switches. Further studies are required to investigate the causal relationships between those factors.
authors.affiliation: Department of Psychiatry, School of Medicine, Vita-Salute University San Raffaele, Via Stamira D'Ancona 20, Milan 20127, Italy. serretti.alessandro@hsr.it
authors.forename: Alessandro
authors.initials: A
authors.lastname: Serretti
authors.forename: Paola
authors.initials: P
authors.lastname: Artioli
authors.forename: Raffaella
authors.initials: R
authors.lastname: Zanardi
authors.forename: David
authors.initials: D
authors.lastname: Rossini
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000523:psychology*; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D003527:Cyclothymic Disorder / Q000188:drug therapy / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio
chemical_list: D000928:Antidepressive Agents