Developmental Risk Relationships between ADHD and Depressive Disorders in Childhood

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that is associated with significant difficulties in the executive control of behaviour and emotions. Risk for depression in ADHD youth is a logical concern. This narrative review examines what is known regarding sources of risk for depression in youth with ADHD in the areas of epidemiology, genetics, neuroanatomy, neuropsychological functioning, social functioning, maltreatment and the effects of psychopharmacologic treatments. Emphasis is placed on longitudinal studies across childhood to maximize relevance to the research question. Findings suggest that comorbidity between ADHD and depression is less than chance would predict in community studies, and shared risk for oppositional defiant disorder accounts for the association that is seen in clinical studies. ADHD and depression share few if any similarities in brain morphology and function. The risk of maltreatment, difficulties in parenting ADHD children and social functioning deficits likely account for substantial risk for depression and should be targets for interventions.