Diagnostic Requirements #

Essential (Required) Features: #

• Presence or history of a single Depressive Episode (see Essential Features).
• There is no history of Manic, Mixed, or Hypomanic Episodes, which would indicate the presence of a Bipolar Disorder.

Severity, Psychotic Symptoms, and Remission Specifiers #

The Depressive Episode in Single Episode Depressive Disorder should be classified according to the severity of the episode or the degree of remission. Moderate and Severe episodes should also be classified according to the presence or absence of psychotic symptoms. (See descriptions of episode severity and psychotic symptoms in Depressive Episodes above.) Available categories are as follows:

• 6A70.0 Single Episode Depressive Disorder, Mild单次发作抑郁障碍，轻度
• 6A70.1 Single Episode Depressive Disorder, Moderate, without psychotic symptoms单次发作的抑郁障碍，中度，不伴精神症状
• 6A70.2 Single Episode Depressive Disorder, Moderate, with psychotic symptoms单次发作的抑郁障碍，中度，伴精神病性症状
• 6A70.3 Single Episode Depressive Disorder, Severe, without psychotic symptoms单次发作的抑郁障碍，重度，不伴精神病性症状
• 6A70.4 Single Episode Depressive Disorder, Severe, with psychotic symptoms单次发作的抑郁障碍，重度，伴精神病性症状
• 6A70.5 Single Episode Depressive Disorder, Unspecified Severity 单次发作抑郁障碍，未特指严重程度
• 6A70.6 Single Episode Depressive Disorder, currently in partial remission单次发作抑郁障碍，目前为部分缓解
• 6A70.7 Single Episode Depressive Disorder, currently in full remission单次发作抑郁障碍，目前为完全缓解
• 6A70.Y Other specified single episode depressive disorder 其他特指的单次发作抑郁障碍
• 6A70.Z Single episode depressive disorder, unspecified未特指的单次发作抑郁障碍

Diagnostic Requirements #

• All diagnostic requirements for a Mild Depressive Episode are currently met.
• There are no delusions or hallucinations during the Depressive Episode.

6A70.1 Single episode depressive disorder, moderate, without psychotic symptoms单次发作的抑郁障碍，中度，不伴精神症状 #

Postcoordination 后组配  #

6A70.2 Single episode depressive disorder, moderate, with psychotic symptoms单次发作的抑郁障碍，中度，伴精神病性症状 #

Postcoordination 后组配  #

Symptomatic and Course Presentations for Mood Episodes in Single Episode Depressive Disorders #

Additional specifiers may be applied to describe the presentation and characteristics of a current Depressive Episode in the context of Single Episode Depressive Disorder. These specifiers indicate other important features of the clinical presentation or of the course, onset, and pattern of Depressive Episodes. These specifiers are not mutually exclusive, and as many may be added as apply. (Note that these same specifiers may also be applied to current Depressive Episodes in the context of Bipolar Type I Disorder or Bipolar Type II Disorder.)

Available specifiers are as follows:

with prominent anxiety symptoms (6A80.0) #

• This specifier can be applied if, in the context of a current Depressive Episode, prominent and clinically significant anxiety symptoms (e.g., feeling nervous, anxious or on edge, not being able to control worrying thoughts, fear that something awful will happen, having trouble relaxing, muscle tension, autonomic symptoms) have been present for most of the time during the episode. If there have been panic attacks during the current Depressive Episode, these should be recorded separately (see below). When the diagnostic requirements for both a Depressive Episode and an Anxiety or Fear-Related Disorder are met, the Anxiety or Fear-Related Disorder should also be diagnosed.

with panic attacks (6A80.1) #

• This specifier can be applied if, in the context of a current Depressive Episode, there have been panic attacks during the past month that occur specifically in response to depressive ruminations or other anxiety-provoking cognitions. If panic attacks occur exclusively in response to such thoughts, the ‘with panic attacks’ specifier should be applied rather than an additional co-occurring diagnosis of Panic Disorder. If some panic attacks over the course of the Depressive Episode have been unexpected and not exclusively in response to depressive thoughts, a separate diagnosis of Panic Disorder should be assigned.

current Depressive Episode persistent (6A80.2) #

• This specifier can be applied if the diagnostic requirements for Depressive Episode are currently met and have been met continuously for at least the past 2 years.

current Depressive Episode with melancholia (6A80.3) #

• This specifier can be applied if, in the context of a current Depressive Episode, several of the following symptoms have been present during the worst period of the current episode:
  • Loss of interest or pleasure in most activities that are normally enjoyable to the individual (i.e., pervasive anhedonia).
  • Lack of emotional reactivity to normally pleasurable stimuli or circumstances (i.e., mood does not lift even transiently with exposure).
  • Terminal insomnia, i.e., waking in the morning 2 hours or more before the usual time.
  • Depressive symptoms are worse in the morning.
  • Marked psychomotor retardation or agitation.
  • Marked loss of appetite or loss of weight.

with seasonal pattern (6A80.4) #

• A substantial majority of Depressive Episodes should correspond with the seasonal pattern.
• A seasonal pattern should be differentiated from an episode that is coincidental with a particular season but predominantly related to a psychological stressor that regularly occurs at that time of the year (e.g., seasonal unemployment).

In the context of Single Episode Depressive Disorder, Depressive Episodes that occur during pregnancy or commencing within about 6 weeks after delivery (referred to as the puerperium) can be identified using one of the following two additional diagnostic codes, depending on whether delusions, hallucinations, or other psychotic symptoms are present. These diagnoses should be assigned in addition to the relevant Depressive Disorder diagnosis.

6E20 Mental or behavioural disorders associated with pregnancy, childbirth or the puerperium, without psychotic symptoms (6E20) #

• This additional diagnostic code should be used for Mood Episodes that arise during pregnancy or commencing within about 6 weeks after delivery that do not include delusions, hallucinations, or other psychotic symptoms. This designation should not be used to describe mild and transient depressive symptoms that do not meet the diagnostic requirements for a depressive episode, which may occur soon after delivery (so-called postpartum blues).

6E21 Mental or behavioural disorders associated with pregnancy, childbirth or the puerperium, with psychotic symptoms #

• This additional diagnostic code should be used for Mood Episodes that arise during pregnancy or commencing within about 6 weeks after delivery that include delusions, hallucinations, or other psychotic symptoms. This designation should not be used to describe mild and transient depressive symptoms that do not meet the diagnostic requirements for a depressive episode, which may occur soon after delivery (so-called postpartum blues).

Note: For the following sections, see also material under Depressive Episode, Manic Episode, Mixed Episode and Hypomanic Episode. Material on Additional Clinical Features, Boundary with Normality (Threshold), Developmental Presentations, and Boundary with Other Disorders and Conditions (Differential Diagnosis) that relates specifically to the Mood Episodes is contained in these sections, whereas material focusing on Single Episode Depressive Disorder overall appears below.

Additional Clinical Features: #

• Suicide risk is significantly higher among individuals diagnosed with Single Episode Depressive Disorder than among the general population.
• Recurrent panic attacks in Single Episode Depressive Disorder may be indicative of greater severity, poorer response to treatment, and greater risk for suicide.
• The presence of Dementia or Disorder of Intellectual Development does not rule out the diagnosis of Single Episode Depressive Disorder, but communication difficulties may make it necessary to rely more than usual on observations made by clinicians or knowledgeable collateral informants for making the diagnosis. Observable symptoms include psychomotor retardation, loss of appetite and weight, and sleep disturbance.
• There is a greater risk of Single Episode Depressive Disorder among individuals with a family history of Single Episode Depressive Disorder or Recurrent Depressive Disorder.
• Co-occurrence with other Mental, Behavioural or Neurodevelopmental Disorders is common, including Anxiety or Fear-Related Disorders, Bodily Distress Disorder, Obsessive-Compulsive or Related Disorders, Oppositional Defiant Disorder, Disorders Due to Substance Use, Eating Disorders, and Personality Disorder.

Course Features: #

• The prevalence of Depressive Disorders significantly increases at puberty with the average age of onset occurring during the mid-20s.
• In the absence of intervention, Depressive Episodes typically last 3 to 4 months with nearly half of affected individuals experiencing symptom reduction within 3 months and the majority experiencing remission within 1 year. Remission and recurrence rates vary widely with most individuals experiencing an average of four Depressive Episodes over their lifetime, and approximately half experiencing a recurrence within the first 5 years. The risk of relapse increases with each subsequent Depressive Episode.
• It is common for depressive symptoms to persist between discrete episodes (i.e., partial remission), with some individuals never experiencing a complete remission of symptoms. This presentation warrants closer attention, because symptom persistence has been associated with shorter time to relapse as well as co-occurrence of other Mental, Behavioural or Neurodevelopmental Disorders including Personality Disorder, Anxiety or Fear-Related Disorders, and Disorders Due to Substance Use.
• Lower rates of recovery are associated with longer duration and severity of symptoms and the presence of psychotic features.
• Individuals with Bipolar Disorders often present initially with a Depressive Episode. Vulnerability factors associated with transition from a Depressive Disorder to a Bipolar Disorder include earlier age at onset, a family history of Bipolar Disorders, and the presence of psychotic symptoms.

Culture-Related Features: #

• The cultural salience of depressive symptoms may vary across social groups as a result of varying cultural ‘scripts’ for the disorder. For example, psychological (e.g., sadness, emotional numbness, rumination), moral (e.g., guilt, worthlessness), social/interpersonal (e.g., lack of productivity, conflictive relationships), hedonic (e.g., decreased pleasure), spiritual (e.g., dreams of dead relatives), or somatic symptoms (e.g., insomnia, pain, fatigue, dizziness) may systematically predominate.
• In some cultural contexts, mood changes are more readily expressed in the form of bodily symptoms (e.g., pain, fatigue, weakness) rather than directly reported as psychological symptoms.
• Some types of symptoms may be considered more shameful or severe according to cultural norms, leading to reporting biases. For example, some cultural groups may emphasize shame more than guilt, whereas in others suicidal behaviour and thinking may be prohibited or highly stigmatized, leading to reporting biases. Also, in some cultural groups, features such as sadness and lack of productivity may be perceived as signs of personal weakness and be under-reported.
• The perceived abnormality or acceptability of depressive symptoms may vary across cultures, affecting symptom detection and treatment acceptability. For example, some social groups or age cohorts may consider depressive symptoms to be normal reactions to adversity, depending on their tolerance of negative emotions or social withdrawal.
• Symptoms attributed to cultural concepts of distress may be evoked when querying about depressive symptomatology. Among Chinese, for example, symptoms of shenjing shuairuo, or weakness of the nervous system (e.g., weakness, headache, bodily aches, fatigue, feeling vexed, loss of face) may be commonly reported. Culturally related symptoms and idioms of distress may complicate detection of Depressive Disorders and assessment of severity, including whether psychotic symptoms are present. Examples include pain in heart, soul loss, aching heart, complaints related to ‘nerves’, and heat inside the body. In some other cultures, a focus on a particular observable behaviour (e.g., ‘thinking too much’) may be what is reported.

Sex- and/or Gender-Related Features: #

• Lifetime prevalence of Depressive Disorders is approximately twice as high for women. Gender differences in prevalence coincide with onset of puberty.
• Although women are more likely to attempt suicide, men are more likely to die by suicide by virtue of using more lethal methods.
• Women with a diagnosis of a Depressive Disorder are more likely to experience co-occurring Anxiety or Fear-Related Disorders, disturbances in appetite, and weight gain whereas it is more common for men to experience co-occurring alcohol and other Disorders Due to Substance Use, poor impulse control, and increased risk-taking behaviour.

Boundaries with Other Disorders and Conditions (Differential Diagnosis): #

• Boundary with Dysthymic Disorder: Single Episode Depressive Disorder is differentiated from Dysthymic Disorder by the number of symptoms and the course of the disorder. Dysthymic Disorder is a chronic and persistent condition, and during the initial period of 2 years necessary to establish the diagnosis, the number and duration of symptoms are not sufficient to meet the diagnostic requirements for a Depressive Episode as required for a diagnosis of Single Episode Depressive Disorder. After this initial period, if the number and severity of symptoms reaches the diagnostic threshold for a Depressive Episode in the context of an ongoing Dysthymic Disorder, both Dysthymic Disorder and Single Episode Depressive Disorder may be diagnosed. Long periods of subthreshold depressive symptoms that occur following Depressive Episodes when there has not been an initial 2-year period of subthreshold symptoms are better diagnosed as Single Episode Depressive Disorder in partial remission or Recurrent Depressive Disorder in partial remission.
• Boundary with Mixed Depressive and Anxiety Disorder: Individuals who present with both depressive and anxiety symptoms more days than not for a period of 2 weeks or more, with neither set of symptoms, considered separately, being sufficiently severe, numerous, or lasting to justify a diagnosis of Single Episode Depressive Disorder or an Anxiety or Fear-Related Disorder may be diagnosed with Mixed Depressive and Anxiety Disorder.
• Boundary with Cyclothymic Disorder: Although in general, depressive periods in Cyclothymic Disorder are not sufficient to meet the diagnostic requirements for a Depressive Episode, there may be instances in which the symptoms are severe enough to constitute a Depressive Episode. In such cases, if there is no history of Hypomanic Episodes, Single Episode Depressive Disorder may be diagnosed, as appropriate, along with Cyclothymic Disorder.
• Boundary with Schizophrenia or Other Primary Psychotic Disorders: The presentation is not better accounted for by a diagnosis of Schizophrenia or Other Primary Psychotic Disorder. Individuals with Single Episode Depressive Disorder can exhibit psychotic symptoms, but these occur only during Depressive Episodes. Conversely, individuals with a diagnosis of Schizophrenia or Other Primary Psychotic Disorder may experience significant depressive symptoms during psychotic episodes. In such cases, if the depressive symptoms do not meet the diagnostic requirements for a Depressive Episode, the specifier ‘with prominent depressive symptoms’ may be applied to the psychotic disorder diagnosis. If all diagnostic requirements for both a Depressive Episode and Schizophrenia are met concurrently or within a few days of each other, the diagnosis of Schizoaffective Disorder should be assigned rather than Single Episode Depressive Disorder. However, a diagnosis of Single Episode Depressive Disorder can co-occur with a diagnosis of Schizophrenia or Other Primary Psychotic Disorder, and both diagnoses may be assigned if the full diagnostic requirements for both disorders are met and psychotic symptoms are present outside of Depressive Episodes.
• Boundary with Anxiety or Fear-Related Disorders: Symptoms of anxiety, including panic attacks, are common in Single Episode Depressive Disorder, and in some individuals may be a prominent aspect of the clinical presentation. In such cases, the specifier ‘with prominent anxiety symptoms’ should be applied to the diagnosis for non-panic anxiety symptoms. If the anxiety symptoms meet the diagnostic requirements for an Anxiety or Fear-Related Disorder, the appropriate diagnosis from the Anxiety or Fear-Related Disorders grouping should also be assigned. For panic attacks, if these occur entirely in the context of anxiety associated with Depressive Episodes in Single Episode Depressive Disorder, they are appropriately designated using the ‘with panic attacks’ specifier. However, if panic attacks also occur outside of symptomatic Mood Episodes and other diagnostic requirements are met, a separate diagnosis of Panic Disorder should be considered. Both specifiers may be assigned if warranted.
• Boundary with Generalized Anxiety Disorder: Generalized Anxiety Disorder and Depressive Episodes in Single Episode Depressive Disorder can share several features such as somatic symptoms of anxiety, difficulty with concentration, sleep disruption, and feelings of dread associated with pessimistic thoughts. Single Episode Depressive Disorder is differentiated by the presence of low mood or loss of pleasure in previously enjoyable activities and other characteristic symptoms of a Depressive Episode (e.g., appetite changes, feelings of worthlessness, recurrent thoughts of death). In Generalized Anxiety Disorder, individuals are focused on potential negative outcomes that might occur in a variety of everyday aspects of life (e.g., family, finances, work) rather than thoughts of worthlessness or hopelessness. Rumination often occurs in the context of Single Episode Depressive Disorder but, unlike in Generalized Anxiety Disorder, is not usually accompanied by persistent worry and apprehension about various everyday aspects of life. Generalized Anxiety Disorder may co-occur with Single Episode Depressive Disorder, but should only be diagnosed if the diagnostic requirements for Generalized Anxiety Disorder were met prior to the onset of or following complete remission of a Depressive Episode.
• Boundary with Adjustment Disorder: Adjustment Disorder is characterized by a maladaptive reaction to identifiable psychosocial stressors, and can include depressive symptoms (e.g., rumination) but does not include a sufficient number and severity of symptoms to meet the requirements for a Depressive Episode. If the adjustment reaction meets the diagnostic requirements for Single Episode Depressive Disorder, even in the presence of identifiable psychosocial stressors, Single Episode Depressive Disorder should be diagnosed rather than Adjustment Disorder.
• Boundary with Oppositional Defiant Disorder: It is common, particularly in children and adolescents, for patterns of noncompliance and symptoms of irritability/anger to arise as part of a Mood Disorder. Specifically, noncompliance may result from a number of depressive symptoms (e.g., diminished interest or pleasure in activities, difficulty concentrating, hopelessness, psychomotor retardation, reduced energy). Oppositional Defiant Disorder often co-occurs with Mood Disorders, and irritability/anger can be a common symptom across these disorders. When the behaviour problems occur primarily in the context of a Depressive Episode, a separate diagnosis of Oppositional Defiant Disorder should not be assigned. However, both diagnoses may be given if the full diagnostic requirements for both disorders are met and the behaviour problems associated with Oppositional Defiant Disorder are observed outside the occurrence of Depressive Episodes.
• Boundary with Insomnia: Individuals experiencing Insomnia may also report depressed mood and may develop other depressive symptoms. However, the breadth and severity of symptoms are generally not sufficient to meet the diagnostic requirements for Single Episode Depressive Disorder.
• Boundary with Secondary Mood Syndrome: A depressive syndrome that is a manifestation of another medical condition (e.g., hypothyroidism) should be diagnosed as Secondary Mood Syndrome rather than Single Episode Depressive Disorder.
• Boundary with Substance-Induced Mood Disorder: A depressive syndrome due to the effects of a substance or medication on the central nervous system (e.g., benzodiazepines), including withdrawal effects (e.g., from stimulants) should be diagnosed as Substance-Induced Mood Disorder rather than Single Episode Depressive Disorder. The presence of continuing mood disturbance should be assessed once the physiological effects of the relevant substance subside.