Early risk factors and attention deficit hyperactivity/disorder (ADHD) developmental trajectories

Attention Deficit/Hyperactivity Disorder (ADHD) is associated with a set of early genetic and environmental risk factors. Genetic risk factors, of which existence is supported by genetically informed (i.e. Twin) and molecular studies, are yet partially identified. They do not constitute diagnostic markers or therapeutic targets for preventive interventions. Early environmental risk factors exist and could represent targets for early interventions. However, their causal nature is not determined yet. In addition, early environmental risk factors are distal factors compared with later risk factors, which makes difficult the understanding of their direct links with the ADHD phenotype. Developmental trajectories of ADHD are interesting to study in order to take into account the dimensional and developmental nature of ADHD. Investigating the link between early risk factors and developmental trajectories could allow a better understanding of their interactions along time. The experiment of preventive interventions of ADHD could lead to disentangle mechanisms and provide new tools to treat ADHD. (C) 2014 Elsevier Masson SAS. All rights reserved.