Neurodevelopmental Disorders: Attention Deficit Hyperactivity Disorder (ADHD)

Attention-deficit/hyperactivity disorder (ADHD) is a highly prevalent, heritable, neurodevelopmental disorder that most often begins in childhood and persists into adulthood. It exacts a high functional, psychological, and economic toll on individuals, families, and society. ADHD has been recognized in both developed and underdeveloped countries worldwide, with prevalence rates that are largely comparable, when similar assessment methods are used. Global perspectives that were once quite divergent are moving toward concordance, based on literature from genetics (candidate gene research, GWAS, and pharmacogenomics), brain imaging (PET, SPECT, MRI, task-based fMRI, and DTI), epidemiological research, and psychological science (clinical psychometrics, neuropsychological/psycho-physics, psychosocial and functional assessment). Here an overview of ADHD is presented based on a comprehensive and updated review of the literature, and clinicians are provided with evidence-based information regarding etiology, diagnostic features, comorbidity, and changing clinical presentations across the lifespan. A comprehensive review of clinical tools that are effective in diagnosis and monitoring treatment are provided. Psychological and neurobiological models of the disorder are examined, and the role of environmental and contextual factors influencing the clinical presentation is considered. Current information is provided regarding evidence-based psychosocial and pharmacological treatments and how to tailor these treatments according to life stage, clinical presentation, and presence of associated features. Finally, possible approaches for treatment refractory patients are considered. Clinical examples are provided.