Depressive disorders

[GarryDrold]

Depressive disorders are characterized by sadness severe enough or persistent enough to interfere with function and often by decreased interest or pleasure in activities. Exact cause is unknown but probably involves heredity, changes in neurotransmitter levels, altered neuroendocrine function, and psychosocial factors. Diagnosis is based on history. Treatment usually consists of drugs, psychotherapy, or both and sometimes electroconvulsive therapy or rapid transcranial magnetic stimulation (rTMS).
The term depression is often used to refer to any of several depressive disorders. Some are classified in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) by specific symptoms:

Major depressive disorder (often called major depression)
Persistent depressive disorder (dysthymia)
Other specified or unspecified depressive disorder

Others are classified by etiology:

Premenstrual dysphoric disorder
Depressive disorder due to another medical condition
Substance/medication-induced depressive disorder

Depressive disorders occur at any age but typically develop during the mid teens, 20s, or 30s (see also Depressive Disorders in Children and Adolescents). In primary care settings, as many as 30% of patients report depressive symptoms, but