Le Trouble Déficit de l'attention/hyperactivité est actuellement un trouble relativement bien connu chez l'enfant et l'adolescent. Mais depuis quelques années, de nombreuses études ont démontré une persistance partielle ou complète de ce syndrome au-delà de l'adolescence. En effet, de nombreux adultes présentent des symptômes similaires à ceux retrouvés chez les enfants. La symptomatologie chez l'adulte est souvent plus marquée par le déficit de l'attention que par l'hyperactivité psychomotrice et l'impulsivité. L'ensemble des symptômes engendre fréquemment un dysfonctionnement des patients tant au niveau social et professionnel qu'au niveau affectif. Le diagnostic différentiel reste difficile en particulier avec les troubles de la personnalité, les troubles anxieux ou les troubles de l'humeur, d'autant plus que les troubles associés sont fréquents. Bien qu'invalidant, il semble que ce trouble soit particulièrement sensible aux différents traitements (psychothérapies et/ou médicaments) qui permettent aux patients une meilleure qualité de vie. L'objectif de cet article est de proposer une synthèse concise des connaissances actuelles sur le trouble déficit de l'attention avec hyperactivité chez l'adulte, tant sur le plan clinique qu'éthiopathogénique.

The Attention-Deficit and Hyperactivity Disorder is frequent and well known in childhood and in child psychiatry. However, this disorder is widely under-diagnosed in adults. There has been a greater interest in this disorder for several decades: Several studies have indicated a persistence of symptoms beyond childhood and adolescence in up to 66% of cases, which leads to a prevalence of 5% in the general population of adults. This disorder is diagnosed on clinical presentation. The diagnostic criteria in adults are facilitated if the first symptoms of this disorder are detected before the age of seven. The symptoms are similar to those observed in children, even thought attention deficits are more frequent than impulsiveness or psychomotor hyperactivity in this population. Very often, patients diagnose their disorder on their own via journals or Internet, and then they try to find a specialist. The DSM-IV and ICD-10 criteria for adults include several items typically found in children suffering from this disorder, and differentiate several subtypes. This paper tries to clarify the functioning of this disorder, with the objective of a better knowledge and treatment for patients who are seriously handicapped by their trouble. Whereas there is a gender ratio of 4:1 (males: females) in children, women are as much concerned as men in the adult forms. The daily life of patients suffering from hyperactivity is disturbed in nearly all fields, including work, relationships and leisure. The disorder can lead to severe consequences for patients and their environment, including loss of work, separations, accidents and chaotic lifestyles. Hyperactivity can be difficult to distinguish from some of the other psychiatric disorders - mostly borderline or dissocial behaviour -, such as bipolar or conduct disorders. However, it can also occur in co-morbidity of any one of these disorders, and this in up to 60% of the cases. Nevertheless, it is important to mention that this disorder is usually present before the onset of the other co-morbid disorders. Multiple etiological factors seem to be implicated in this disorder. Several studies have highlighted the possible contribution of perinatal, neurobiological, neuroanatomical, neuropsychological and genetic factors. The abnormality most explored is the imbalance between noradrenergic and dopaminergic systems. Similarly, genetic studies underline the aberrations found in the dopamine transporter gene and in the D2 and D4 receptor genes. For general practitioners, social workers, forensic institutions or courts, it is important to realise that these patients can beneficiate from an adequate and effective treatment. Pharmacological treatments are the same as the ones for children, they include méthylphénidate and atomoxetine but also antidepressants and antihypertonics. Beside pharmacotherapy, psycho-education can significantly improve symptoms and results in improving self-management of daily life difficulties.