What is Depressive Disorder Not Otherwise Specified?

Introduction

Depressive Disorder Not Otherwise Specified (DD-NOS) is designated by the code 311 in the DSM-IV for depressive disorders that are impairing but do not fit any of the officially specified diagnoses. According to the DSM-IV, DD-NOS encompasses “any depressive disorder that does not meet the criteria for a specific disorder.” In the DSM-5, it is called unspecified depressive disorder.

Refer to Dissociative Disorder Not Otherwise Specified (DDNOS).

Background

Examples of disorders in this category include those sometimes described as minor depressive disorder and recurrent brief depression.

“Depression” refers to a spectrum of disturbances in mood that vary from mild to severe and from short periods to constant illness. DD-NOS is diagnosed if a patients symptoms fail to meet the criteria more common depressive disorders such as major depressive disorder or dysthymia. Although DD-NOS shares similar symptoms to dysthymia, dysthymia is classified by a period of at least 2 years of constantly recurring depressed mood, where as DD-NOS is classified by much shorter periods of depressed moods.

For most people who suffer the condition, their life will be significantly affected. DD-NOS can make many aspects of a person’s daily life difficult to manage, inhibiting their ability to enjoy the things that used to make them happy. Sufferers of the disorder tend to isolate themselves from their friends and families, lose interest in some activities, and experience behavioural changes and sleeping disorders. Some sufferers also experience suicidal tendencies or suicide attempts. In addition to having these symptoms, a diagnosis of DD-NOS will only be made if the symptoms cause significant distress or impairment in social, occupational, or other important areas of functioning. For the diagnosis to be accurate, a psychiatrist is required to spend extensive time with the patient.

Symptoms of the disorder may arise due to several reasons. These include:

  • Distress due to medical conditions.
  • Environmental effects and situations.

However, the effects of drugs or medication or bereavement are not classified under the diagnosis.

A person will not be diagnosed with the condition if they have or have had any of the following: a major depressive episode, manic episode, mixed episode or hypomanic episode.

A diagnosis of the disorder will look like: “Depressive Disorder NOS 311”.

Concerns

Accurately assessing for a specific Depressive Disorder diagnosis requires an expenditure of time that is deemed unreasonable for most primary care physicians. For this reason, physicians often use this code as a proxy for a more thorough diagnosis. There is concern that this may lead to a “wastebasket” mindset for certain disorders. In addition reimbursement through Medicare may be lower for certain non specific diagnosis.

Treatment

It is possible for this disorder to progress over time. A patient suffering from the disorder can improve the condition with treatments. There are several types of therapies that may improve the condition, but depending on a patient’s experience of the disorder or the cause of the disorder, treatments will vary.

  • Psychotherapy including behaviour therapy, Gestalt therapy, Adlerian therapy, psychoanalytic therapy and existential therapy.
  • Pharmacotherapy through medications including antidepressants.

What is Recurrent Brief Depression?

Introduction

Recurrent brief depression (RBD) defines a mental disorder characterised 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 5-7 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.

Prevalence

The lifetime prevalence of RBD has been estimated at 2.6-10.0%, and the one-year prevalence at 5.0-8.2%. The WHO 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 lifetime of RBD only to be about 2%.

Brief History

Disorders characterised by periods with depressive episodes lasting hours to days have been described since 1852 and have been labelled “periodic melancholia”, “intermittent depressive disorder” or “very brief depression”. The third version of the Diagnostic and Statistical Manual of Mental Disorders (1980), which relied heavily on findings from studies conducted in psychiatric in- and out-patient settings, required at least 14 days duration for a diagnosis of depression. No diagnostic category was allocated a depressive episode of shorter duration. Thus, intermittent depressive disorder, included in the Research Diagnostic Criteria (1975) was considered to identify minor versions of major depression (“minor depression”) and not included in the DSM-III.

However, based on data from epidemiological studies, the Swiss psychiatrist and researcher, Jules Angst, coined the concept “recurrent brief depression” (RBD) and provided diagnostic criteria for this type of mood disorder in 1985. Several other European studies independently confirmed the occurrence of RBD in the general population and clinical samples. RBD was thus included in the 10th classification of mental and behavioural disorders (ICD-10 F38.1) published by the World Health Organisation in 1992 (WHO, 1992; WHO, 1993). Less frequent episodes of brief depressions were labelled infrequent brief depression and not included in ICD-10. The American classification system of mental disorders, DSM-IV (1994), provided provisional diagnostic criteria for RBD, but decided to await further studies before including RBD in the classification system. The fate of RBD in DSM-5, expected to occur in 2013, is not known.

Causes

The cause (aetiology) 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 subgroup of patients with RBD has temporal lobe epilepsy.

Diagnosis

From the International Statistical Classification of Mental and Behavioral Disorders:

F33 Recurrent depressive disorder

  • G1. There has been at least one previous episode, mild (F32.0), moderate (F32.1), or severe (F32.2 or F32.3), lasting a maximum of two weeks and separated from the current episode by at least two months free from any significant mood symptoms.
  • G2. At no time in the past has there been an episode meeting the criteria or hypomanic or manic episode (F30.-).
  • G3. Most commonly used exclusion criteria: the episode is not attributable to psychoactive substance use (F1) or any organic mental disorder, in the sense of F0. It is recommended to specify the predominant type of previous episodes (mild, moderate, severe, uncertain).

F33.0 Recurrent depressive disorder, current episode mild

  • A. The general criteria for recurrent depressive disorder (F33) are met.
  • B. The current episode meets the criteria for depressive episode, mild severity (F32.0).
  • A fifth character may be used to specify the presence of the somatic syndrome, as defined in F32, in the current episode:
    • F33.00 without somatic syndrome.
    • F33.01 with somatic syndrome.

F33.1 Recurrent depressive disorder, current episode moderate

  • A. The general criteria for recurrent depressive disorders (F33) are met.
  • B. The current episode meets the criteria for depressive episode, moderate severity (F32.1).
  • A fifth character may be used to specify the presence of the somatic syndrome, as defined in F32, in the current episode:
    • F33.10 without somatic syndrome
    • F33.11 with somatic syndrome.

F33.2 Recurrent depressive disorder, current episode severe without psychotic symptoms

  • A. The general criteria for recurrent depressive disorders (F33) are met.
  • B. The current episode meets the criteria for severe depressive episode without psychotic symptoms (F32.2).

F33.3 Recurrent depressive disorder, current episode severe with psychotic symptoms

  • A. The general criteria for recurrent depressive disorders (F33) are met.
  • B. The current episode meets the criteria for severe depressive episode with psychotic symptoms (F32.3). A fifth character may be used to specify whether the psychotic symptoms are congruent or incongruent with the mood:
    • F33.30 with mood congruent psychotic symptoms.
    • F33.31 with mood incongruent psychotic symptoms.

F33.4 Recurrent depressive disorder, currently in remission

  • A. The general criteria for recurrent depressive disorder (F33) have been met in the past.
  • B. The current state does not meet the criteria for a depressive episode (F32.-) of any severity, or for any other disorder in F3 (the patient may receive treatment to reduce the risk of further episodes).

F33.8 Other recurrent depressive disorders.

F33.9 Recurrent depressive disorder, unspecified.

Treatment

Both psychotherapy as well as different drugs (e.g. serotonin reuptake inhibitors – SSRIs or mood stabilisers, e.g. lithium, antiepileptics) have been suggested as treatments. However, no randomised controlled treatment trial of RBD has been conducted.