title: Phenotypic spectra of bipolar disorder in responders to lithium versus lamotrigine.
abstract: OBJECTIVE
  We conducted a study of clinical presentation and family history in patients responsive to either of two commonly used mood stabilizers, lithium and lamotrigine.
  
  
  METHODS
  The sample included 164 subjects from 21 families of bipolar probands, 14 responders to lithium and seven to lamotrigine. Diagnostic information on first-degree relatives was obtained in a blind fashion through a combination of direct interviews (SADS-L) and family history assessments (FH-RDC).
  
  
  RESULTS
  The probands differed with respect to clinical course (episodic in the lithium group, rapid cycling in the lamotrigine group), and comorbidity (panic attacks and substance abuse in the lamotrigine group). The relatives of lithium responders had significantly higher risk of bipolar disorder while relatives of lamotrigine responders had higher prevalence of schizoaffective disorder, major depression and panic attacks.
  
  
  CONCLUSIONS
  These findings suggest that lithium- and lamotrigine-responsive patients differ with respect to course of illness, comorbidity and family history and may represent distinct subtypes of bipolar disorder.
authors.affiliation: Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Passmore
authors.forename: Julie
authors.initials: J
authors.lastname: Garnham
authors.forename: Anne
authors.initials: A
authors.lastname: Duffy
authors.forename: Marsha
authors.initials: M
authors.lastname: MacDougall
authors.forename: Alana
authors.initials: A
authors.lastname: Munro
authors.forename: Claire
authors.initials: C
authors.lastname: Slaney
authors.forename: Andrew
authors.initials: A
authors.lastname: Teehan
authors.forename: Martin
authors.initials: M
authors.lastname: Alda
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018692:Antimanic Agents / Q000627:therapeutic use*; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy* / Q000235:genetics*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D000077213:Lamotrigine; D016651:Lithium Carbonate / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014227:Triazines / Q000627:therapeutic use*
chemical_list: D018692:Antimanic Agents; D014227:Triazines; D016651:Lithium Carbonate; D000077213:Lamotrigine