Sleep deprivation as a method of chronotherapy in the treatment of depression.

Disturbances of circadian rhythms play an important role in the pathogenesis of affective illnesses, and their normalisation with methods of chronotherapy might become an important element of therapeutic treatment. Chronotherapy is based on a controlled exposure to environmental stimuli which affect biorhythms. One of the chronotherapeutic methods is sleep deprivation (SD). The article discusses the present status of SD in psychiatry, its methods and application in depression treatment. Presently the most recommended pattern is combining total sleep deprivation (TSD), sleep phase advance (SPA), pharmacotherapy, and sometimes also phototherapy. Such proceedings have proven short-term and long-term effectiveness, and they may also have beneficial effect in drug resistant depression. Among the therapeutic mechanisms of the sleep deprivation treatment, the following are influenced: catecholaminergic, serotonergic and glutamatergic neurotransmission, neurotrophic factors (mainly the brain-derived neurotrophic factor - BDNF), the immune system, the endocrine system, metabolism of some brain structures (mostly the prefrontal cortex) and gene expression related to biological clock. On the grounds of the efficiency, simplicity and safety of this method, authors think that SD in its modern version with SPA should be used more often as an element of depression treatment.