Daley D, et al. - Given that studies estimating the economic burden of attention Deficit Hyperactivity Disorder (ADHD) vary considerably in reported costs, typically focus on health outcomes only, lack adequate control and fail to correct for the influence of genetic and shared environmental factors, researchers sought to reach a fuller understanding of the economic burden of ADHD overcoming these limitations. The Danish National Registers yielded data of 5269 adults with a diagnosis of ADHD in adulthood who had not received a diagnosis in childhood. The final cohort comprised 460 sibling dyads following exclusion of cases with missing data, comorbid diagnoses, and cases without a same-sex sibling free of any diagnosed psychiatric diagnoses. Considerably lower disposable income and payment of less tax were reported for adults with ADHD vs their siblings. In addition, ADHD adults received more state benefits, had higher costs for health, social care, and crime. For the year 2010, they noted the total average costs difference of 20,134 euros more than their sibling for each adult with ADHD. These findings suggest considerable costs are borne by the individual and the state in correlation to ADHD.