Depressive disorders

Depressive disorders are highly prevalent and both clinically and etiologically heterogeneous. There are multiple etiological pathways to depression, which change as a function of development and are also shared by other mental and general medical disorders. Depressive disorders have a variable course, and are particularly common in females, with the prevalence increasing markedly in adolescence and young adulthood. Both genetic and environmental factors make significant contributions to depressive disorders, which are associated with a variety of psychological and biological abnormalities. A number of biological and psychosocial treatments are moderately effective in treating depressive disorders and maintaining remission. Unfortunately, many patients do not, or only partially, respond to existing treatments, hence much work remains in order to understand the origins of depressive disorders, and develop more effective approaches to prevention and treatment.