title: A comparison of comorbid patterns in treatment-resistant unipolar and bipolar depression.
abstract: OBJECTIVE
  To examine the occurrence of concomitant psychiatric disorders in patients with treatment-resistant unipolar and bipolar depression.
  
  
  METHODS
  Forty-nine patients participated as subjects. Twenty-four (49%) had unipolar depression and 25 (51%) had bipolar depression using DSM-III-R criteria. Structured clinical interviews were conducted with all patients. Chart reviews and interviews with family members were also carried out. Information relating to both current and lifetime diagnoses was obtained.
  
  
  RESULTS
  Of the entire sample, 75.5% were found to have at least one other Axis I diagnosis and 46.9% had at least two additional Axis I diagnoses. The unipolar group had significantly more current comorbid diagnoses. When type of diagnoses was examined, unipolar patients had significantly more anxiety diagnoses at the time of the index episode, and over their entire lifetime. Bipolar patients had significantly more lifetime substance abuse diagnoses.
  
  
  CONCLUSIONS
  Axis I comorbidity appears to be differentially associated with treatment resistance in unipolar and bipolar depression.
authors.affiliation: Mood Disorders Unit, London Psychiatric Hospital, Ontario.
authors.forename: V
authors.initials: V
authors.lastname: Sharma
authors.forename: D
authors.initials: D
authors.lastname: Mazmanian
authors.forename: E
authors.initials: E
authors.lastname: Persad
authors.forename: K
authors.initials: K
authors.lastname: Kueneman
mesh_terms: D000328:Adult; D000928:Antidepressive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000453:epidemiology / Q000523:psychology; D015897:Comorbidity; D003866:Depressive Disorder / Q000188:drug therapy* / Q000453:epidemiology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D010552:Personality Assessment; D011569:Psychiatric Status Rating Scales; D012008:Recurrence
chemical_list: D000928:Antidepressive Agents