title: Risk factors for rapid cycling in bipolar disorder.
abstract: OBJECTIVE
  The aim of this study was to investigate the clinical factors associated with the development of rapid cycling, as well as to elucidate the role of antidepressants.
  
  
  METHODS
  The present study (NCT01503489) is a prospective, naturalistic cohort study conducted in a sample of 289 patients diagnosed with bipolar disorder followed and treated for up to 14 years. The patients were divided into two groups on the basis of the development of a rapid cycling course (n = 48) or no development of such a course (n = 241), and compared regarding sociodemographic, clinical, and outcome variables.
  
  
  RESULTS
  Among the 289 patients, 48 (16.6%) developed a rapid cycling course during the follow-up. Several differences were found between the two groups, but after performing Cox regression analysis, only atypical depressive symptoms (p = 0.001), age at onset (p = 0.015), and number of suicide attempts (p = 0.030) persisted as significantly associated with the development of a rapid cycling course.
  
  
  CONCLUSIONS
  The development of rapid cycling during the course of bipolar disorder is associated with a tendency to chronicity, with a poorer outcome, and with atypical depressive symptomatology. Our study also suggests that the development of rapid cycling is associated with a higher use of antidepressants.
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Marc
authors: M
authors: Valentí
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Isabella
authors: I
authors: Pacchiarotti
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.|Department of Psychiatry, Facultad de Medicina, Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.
authors: Juan
authors: J
authors: Undurraga
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: C Mar
authors: CM
authors: Bonnín
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Dina
authors: D
authors: Popovic
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: José M
authors: JM
authors: Goikolea
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Carla
authors: C
authors: Torrent
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Diego
authors: D
authors: Hidalgo-Mazzei
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Francesc
authors: F
authors: Colom
authors: Bipolar Disorders Program, Clinical Institute of Neurosciences, Hospital Clínic Barcelona, IDIBAPS, CIBERSAM, University of Barcelona, Barcelona, Catalonia, Spain.
authors: Eduard
authors: E
authors: Vieta
mesh_terms: D000328:Adult; D017668:Age of Onset; D000928:Antidepressive Agents / Q000627:therapeutic use; D018692:Antimanic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy / Q000453:epidemiology / Q000523:psychology*; D015331:Cohort Studies; D003863:Depression / Q000453:epidemiology / Q000523:psychology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013406:Suicide, Attempted / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D000928:Antidepressive Agents; D018692:Antimanic Agents
keywords: antidepressants; bipolar disorder; rapid cycling