Author's reply

We thank our colleagues for their interest in our paper, and agree with them of the importance of careful diagnosis. We disagree though that primarily diagnosing bipolar disorder and underdiagnosing ADHD accounts for the high incidence of mania in the context of high mood stabiliser use. Our study was an incidence study with adults; therefore, by definition, all those who experienced onset of mania within the 2-year period did not have mania at the first time point, and all those who experienced onset of a bipolar depressive episode in the 2-year period had previously had a manic episode that had resolved. Despite some similarities in symptoms between mania and ADHD, there are also key differences: bipolar disorder is a cyclical disorder (hence, with onset of episodes and remission from them) whereas ADHD is not; and ADHD has onset in early childhood so could not account for the onset of new manic psychopathology in these adult participants. The 15 of 651 participants with ADHD had this consistently across the 2-year period. The psychiatric assessments we conducted for the purpose of our study were detailed and included an instrument to detect hyperkinetic disorders, developmental histories, were undertaken by two consultant learning disabilities psychiatrists and all were case-conferenced to apply the four sets of diagnostic criteria. We restate our evidenced-view that the incidence of mania is higher in adults with intellectual disabilities than in the general population, despite the high use of mood stabilisers.