title: Depressive symptoms and family history in seasonal and nonseasonal mood disorders.
abstract: OBJECTIVE
  The authors' goal was to compare the symptoms and family history of seasonal affective disorder with those of nonseasonal mood disorders.
  
  
  METHODS
  From a subspecialty mood disorders clinic, 34 patients with major depression, seasonal pattern (seasonal affective disorder), diagnosed with DSM-III-R criteria, were matched in age, sex, and diagnostic subtype (recurrent unipolar, bipolar I, or bipolar II) to 34 patients with nonseasonal mood disorders. Data on symptoms during the most recent depressive episode were obtained by chart review and compared by using chi-square tests. Family history data for first-degree relatives of patients with seasonal and nonseasonal mood disorders were gathered by using the family history method, and diagnoses were based on Family History Research Diagnostic Criteria.
  
  
  RESULTS
  Patients with seasonal affective disorder reported significantly more hypersomnia, hyperphagia, and weight gain and reported less suicidal ideation and morning worsening of mood than the patients with nonseasonal mood disorders. No differences were found in family histories of mood disorders, other psychiatric disorders, and any psychiatric disorder between the groups with seasonal versus nonseasonal mood disorders. Alcoholism was found more frequently in the relatives of the patients with seasonal affective disorder.
  
  
  CONCLUSIONS
  Differences in symptoms between seasonal and nonseasonal mood disorders provide some support for seasonal affective disorder as a diagnostic subtype of mood disorders. However, the genetic loading for mood disorders (of unspecified seasonality), as determined by the family history method, is similar for seasonal and nonseasonal mood disorders.
authors.affiliation: Department of Psychiatry, University of British Columbia, Vancouver, Canada.
authors.forename: J M
authors.initials: JM
authors.lastname: Allen
authors.forename: R W
authors.initials: RW
authors.lastname: Lam
authors.forename: R A
authors.initials: RA
authors.lastname: Remick
authors.forename: A D
authors.initials: AD
authors.lastname: Sadovnick
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D001835:Body Weight; D002940:Circadian Rhythm; D015897:Comorbidity; D003866:Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D003937:Diagnosis, Differential; D005190:Family; D001068:Feeding and Eating Disorders / Q000175:diagnosis; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D016574:Seasonal Affective Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D012893:Sleep Wake Disorders / Q000175:diagnosis; D013405:Suicide / Q000523:psychology