[Anxiety syndromes: clinical features and classification].

Anxiety disorders are frequent in general medicine but often underdiagnosed due to their frequent somatic symptomatology. Exploring their psychological dimension will help their detection and evaluating their behavioral dimension will allow to determine their functional impact, at times invalidating. Present classifications are mainly based upon their cardinal symptoms (panic attacks, phobias, obsession-compulsion, uncontrolable anxious ruminations) and are used as references for clinical research aimed at exploring their mechanisms and treatment. Early diagnosis and treatment of anxiety disorders are crucial since they represent an important risk factor for the secondary development of depressive episodes.