Attention Deficit Hyperactivity Disorder and Anxiety: Is There an Association with Neurodevelopmental Deficits?

Objective: The co-occurrence of attention deficit hyperactivity disorder (ADHD) and anxiety is a well-established clinical observation. However, its status as a clinical construct is debated. We review the prevalence of ‘ADHD and anxiety’, its definitions, and its clinical correlates and we hypothesise that neurodevelopmental deficits may be increased in ‘ADHD and anxiety’. Method: The authors identified empirical studies in the psychiatric and psychological literature. The search categories included hyperactivity, attention deficit hyperactivity disorder, attention deficit disorder and anxiety. Results: ‘ADHD and anxiety’ is considerably more common in clinical than epidemiological samples. There are a range of definitions which address the situational variation in both ADHD and anxiety symptoms and the use of categorical and continuous variables to define them. Yet the nature of the anxiety is still unclear. It is associated with a poor response to psychostimulant medication treatment, and alternative pharmacotherapy approaches have been suggested. There is a controversy about whether neurodevelopmental deficits are associated with hyperactivity alone, or anxiety, or both. Conclusions: ‘ADHD and anxiety’ is important clinically because it is common and less responsive to psychostimulant medication. Important research issues include its heterogeneity which necessitates the collection of parent, teacher, and child self-reports of symptoms' presence or absence and the hypothesis that neurodevelopmental deficits may be increased in this group of children.