Relationship of parent and child informants to prevalence of mania symptoms in children with a prepubertal and early adolescent bipolar disorder phenotype.

OBJECTIVE: A controversy regarding pediatric bipolar disorder is whether to use child in addition to parent informants. To investigate this issue, the authors conducted a study comparing separate child and parent interview data for child bipolar disorder.
METHOD: Responses on the Washington University in St. Louis Kiddie Schedule for Affective Disorders and Schizophrenia from 93 child and 93 parent informants were compared by using kappa statistics. Research nurses, blind to subject information, separately interviewed parents about their children and children about themselves. Different nurses were used for the parent and child in each family to avoid bias from the same research nurse interviewing a child after interviewing that child's parent. Mania was defined by DSM-IV criteria, with at least one of the two cardinal symptoms of mania (elated mood and/or grandiosity), to avoid diagnosing mania by symptoms that overlapped with those for attention deficit hyperactivity disorder (ADHD).
RESULTS: Parent-child concordance was poor to fair for all cardinal and noncardinal mania symptoms. Kappas were not significantly different by age within the 7-14-year-old age range.
CONCLUSIONS: Symptoms endorsed by just the child included substantial proportions of bipolar symptoms that have been shown to best differentiate mania from ADHD (i.e., elation, grandiosity, flight of ideas, racing thoughts, decreased need for sleep). These findings support the need for child informants in research on prepubertal and early adolescent bipolar disorder in children ages 7-14. Differences in mania symptom profiles between investigative groups may be, in part, due to whether child informants were assessed.