Recurrent brief depression

Recurrent brief depression (RBD) defines a mental disorder characterized by intermittent depressive episodes, not related to menstrual cycles in women, occurring between approximately 6-12 times per year, over at least one year or more fulfilling the diagnostic criteria for major depressive episodes (DSM-IV and ICD-10) except for duration which in RBD is less than 14 days, typically 2–4 days. Despite the short duration of the depressive episodes, such episodes are severe and suicidal ideation and impaired function is rather common. The majority of patients with RBD also report symptoms of anxiety and increased irritability. Hypersomnia is also rather frequent. About 1/2 of patients fulfilling diagnostic criteria for RBD may have additional short episodes of brief hypomania which is a severity marker of RBD. RBD may be the only mental disorder present, but RBD may also occur as part of a history of recurrent major depressive episodes or bipolar disorders. RBD is also seen among some patients with personality disorders.

The lifetime prevalence of RBD has been estimated at 2.6 to 10.0%, and the one-year prevalence at 5.0-8.2%. The World Health Organization project on "Psychological problems in general health care", which was based on primary care samples, reported a one-year prevalence of 3.7 – 9.9%. However none of these studies differentiate between RBD with and without a history of other mood disorders (e.g. major depression). DSM-IV field trial estimated the life-time of RBD only to be about 2%.

The cause (etiology) of RBD is unknown, but recent findings may suggest a link between RBD and bipolar disorders, pointing to the importance of genetic factors. A small sub-group of patients with RBD has temporal lobe epilepsy.

From the International Statistical Classification of Mental and Behavioral Disorders:

F33 Recurrent depressive disorder

F33.0 Recurrent depressive disorder, current episode mild

F33.1 Recurrent depressive disorder, current episode moderate

F33.10 without somatic syndrome

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