Attention deficit hyperactivity disorder with bipolar disorder in girls: further evidence for a familial subtype?

Background: To clarify, the nosologic status of girls with attention deficit hyperactivity disorder (ADHD) who also satisfy diagnostic criteria for bipolar disorder (BPD). Methods: Using blind raters and structured psychiatric interviews, we examined 140 girls with ADHD, 122 non-ADHD comparisons and their 786 first degree relatives. Analyses tested specific hypotheses about the familial relationship between ADHD and bipolar disorder in girls. Results: After stratifying our ADHD sample into those with and without BPD, we found that: (1) relatives of both ADHD subgroups were at significantly greater risk for ADHD than relatives of non-ADHD controls, (?) the two subgroups did not significantly differ in their relatives' risk for ADHD; (3) an elevated risk for bipolar disorder was observed among relatives when the proband child had BPD but not ADHD alone; (4) weak evidence of cosegregation between ADHD and BPD, and (5) no evidence of a trend for random mating between ADHD parents and those with mania. Limitations: Limitations of this study include the lack of direct interviewing of probands and the limited number of ADHD/BPD probands available. Conclusions: These Findings extend to girls what was previously documented in boys and suggest that comorbid ADI-ID with BPD in girls is familially distinct from other forms of ADHD and may be related to what others have termed childhood onset BPD. Future work could determine: if this subgroup has a characteristic course, outcome and response to treatment. (C) 2001 Elsevier Science B.V. All rights reserved.