Comorbid anxiety in phenotypes of pediatric bipolar disorder.
OBJECTIVE
There has been limited research on anxiety in pediatric bipolar disorder (BPD). Adult BPD studies suggest comorbid anxiety disorders are common and impact treatment outcome. We explored the association of comorbid anxiety with two phenotypes of pediatric BPD.


METHODS
We studied two groups of children. The first group (BPD; N = 31) represents the "narrow phenotype" of pediatric BPD, meeting stringent DSM-IV criteria for mania, including duration and elevated/expansive mood. The second group (ED; N = 32) exhibited chronic, non-episodic irritability without elation or grandiosity ("broad phenotype").


RESULTS
Both samples demonstrate high prevalence of anxiety (BPD 77.4%; ED 46.9%). In the BPD sample, anxiety predates BPD onset, and those with comorbid anxiety have earlier age of onset of BPD than those without. Children with BPD plus anxiety have more hospitalizations than those without anxiety. ED subjects with and without comorbid anxiety did not differ with respect to onset of ED symptoms or number of hospitalizations.


CONCLUSIONS
Narrow and broad phenotype BPD children have high rates of comorbid anxiety, although only in the narrow phenotype group is comorbid anxiety associated with greater functional impairment BPD plus comorbid anxiety may represent a particularly severe phenotype of pediatric BPD.
Dickstein
Daniel P
DP
Mood and Anxiety Disorders Program, Pediatrics and Developmental Neuropsychiatry Branch, National Institute of Mental Health, Bethesda, Maryland 20892-1255, USA. Dicksted@mail.nih.gov
Rich
Brendan A
BA
Binstock
Anna B
AB
Pradella
Anne G
AG
Towbin
Kenneth E
KE
Pine
Daniel S
DS
Leibenluft
Ellen
E
D000293:Adolescent; D017668:Age of Onset; D001008:Anxiety Disorders / Q000150:complications* / Q000453:epidemiology* / Q000523:psychology; D001714:Bipolar Disorder / Q000150:complications* / Q000453:epidemiology* / Q000523:psychology; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003627:Data Interpretation, Statistical; D004644:Emotions; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D010641:Phenotype; D011569:Psychiatric Status Rating Scales; D011619:Psychotropic Drugs / Q000627:therapeutic use; D012737:Sex Factors; D013405:Suicide / Q000523:psychology
D011619:Psychotropic Drugs