Dysthymic Disorder Criteria And Clinical Features

Dysthymia, which the DSM-5 refers to as persistent depressive disorder, is a separate type of depression characterized by symptoms that last for at least two years (one year in children) but are milder than those of major depressive disorder.

History Of Dysthymia

"Dysthymia" (a term coined in 1980) comes from "ill humored". Dysthymia was formerly considered a subtype of "neurotic depression," the general term under which these people were classified.  Dysthymia is a sub-affective illness characterized by symptoms that resemble depression but are less severe. The disorder typically manifests as a chronic condition with a sneaky onset that usually starts in childhood or adolescence.

Family History

Patients frequently have a family history of bipolar and depressive illnesses, which supports dysthymia as the main mood disorder.

Clinical Presentation-Social Adjustment

One way that dysthymia differs from major depressive disorder is that its sufferers typically continue to operate in society in a fairly stable manner.
They may seem committed to their work, but they frequently overlook other aspects of life because they are overcompensating for their depression symptoms.  This results in "monothematic existences," when patients struggle to participate in social, familial, or recreational activities but heavily invest in their profession.

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Impact on Patient Behavior and Seeking Help

Behavioral Patterns: Patients may choose not to seek medical attention, attributing their commitment to their jobs to inadvertently ignoring other facets of life. This could result in interpersonal difficulties, particularly in marriages. 

Mono-categorical Existence: This phrase describes a patient who obsesses about work to the exclusion of other aspects of their lives, putting stress on their relationships with others and their own well-being.

Course-Early Onset

Typically, dysthymia appears early in life, usually starting in childhood, adolescence, or by the early twenties. Before the age of 25, over 50% of people had a sneaky, gradual start of symptoms. 

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Risk of Other Mood Disorders

Dysthymia patients are more likely to experience other mood problems in the future.  Less than 5% may develop bipolar I disorder, 15% may advance to bipolar II disorder, and 20% may develop severe depressive disorder.  It's critical to keep an eye on these patients in case they go on to develop other mood disorders.

Episodes of Hypomania

Hypomanic episodes are a possibility for certain dysthymia patients, but full-blown manic episodes or bipolar I disease are less prevalent; bipolar II disorder is more frequently seen.

Late Onset Subtype

In contrast to the more typical early onset appearance, this is less common and less clinically characterized, usually affecting middle-aged to geriatric populations. It is frequently detected through community-based epidemiological research. 

Course And Patterns

Subtle onset and paired depression  Dysthymia typically progresses slowly, potentially culminating in the years or decades later superimposition of a major depressive episode. This condition, known as "double depression," occurs when a patient has recurrent bouts of dysthymic symptoms, a major depressive episode, and then a return to dysthymia. This pattern of twofold depression, in which dysthymia and major depressive episodes recur cyclically, may be present in about 40% of patients with major depressive disorder. 

Comprehensive treatment necessitates the identification of dysthymic symptoms concurrent with major depressive episodes. While major depressive episodes are frequently the focus of attention, underlying dysthymia must also be addressed because of its substantial influence on psychiatric disability and overall prognosis.

Dysthymia is indicated by the figure, which depicts a two-year history of depressive symptoms that are below the major depressive episode threshold. Another course entails a chronic presentation where patients report distress persisting for a longer duration, often subjective with more reported symptoms than observable signs, termed characterological depression. • Afterwards, the patient may progress to experience major depressive episodes, representing double depression.

Clinical Picture

Dysthymia and major depressive disorder (MDD) are comparable in their symptoms, but they usually vary in the percentage of reported symptoms to visible indicators.  Dysthymia patients frequently report subjectively more symptoms than objective evidence, such as disturbed appetite or psychomotor agitation, during clinical examinations. 

Dysthymia usually manifests as a persistent low grade of depression that has a long-standing, erratic course. It can manifest in a variety of ways, occasionally with anxiety symptoms as well. It is sometimes diagnosed as secondary or anxious dysthymia, in conjunction with anxiety disorder. Even in the presence of anxiety, dysthymia must be treated as a main mood disorder. 

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Evidence For Dysthymia As A Primary Mood Disorder

1. Sleep EEG Patterns: Individuals with dysthymia frequently have sleep patterns that are comparable to those observed in major depressive disorders, pointing to commonalities between the two and implying that dysthymia is a main mood disease.
2. Familial Affective Disorders: Dysthymia's classification as a main mood disorder is further supported by the high incidence of familial affective disorders or depressive temperaments in those who have it, highlighting the condition's family link with mood disorders.

Diagnostic Criteria

Length of Symptoms: According to the diagnostic criteria, a person must have mood swings that are at least two years long in adults or one year long in children and adolescents, and they must manifest on most days throughout this time. 

Associated Symptoms: In addition to a melancholy mood, two or more of the following requirements must be met, such as: o An increase or reduction in appetite
o Disturbances in sleep (more or less)
o Lack of hope o Low energy levels
o Low self-esteem
o Diminished capacity for focus or making decisions
o Mnemonic ASHES CUP

DSM-5 includes specific specifiers related to the presence of major depressive disorder criteria within dysthymia. These include:

1. Pure Dysthmic Syndrome
2. Persistent Major Depressive Episode
3. Intermittent Major Depressive Episode with current episode
4. Intermittent Major Depressive Episode without current episode

Other Criteria’s

No history of manic or hypomanic episodes: o Never satisfied the requirements for cyclothymia,  Exclusion of Psychotic diseases: Acute psychotic episodes or psychotic diseases such as schizophrenia should not be linked to dysthymia symptoms.  Non-Attributability to Other disorders: o Substance addiction, including abusing alcohol, cocaine, or marijuana, as well as any other medical disorders like hypothyroidism, should not be the cause of dysthymia symptoms. 

Treatment for the medical disease distinguishes it from dysthymia based on improvement in symptoms.  Functional Impairment: Although dysthymia produces distress, it does not produce the same level of functional impairment as major depressive disorder (MDD), but it nevertheless results in distress or impairment that is clinically significant in a number of areas of life.

Specifiers

Early and Late Onset Specifiers: The DSM-5 has specifiers that classify dysthymia as early onset if it appears before the age of 21 and late onset if it appears after.  No specifier for catatonia is present in dysthymia, in contrast to severe depressive illness.

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Comorbidity with Substance Use Disorder

Comorbid drug use disorder may be present in patients with dysthymia as a result of attempts to self-medicate their chronic depression.Due to the possibility of overlapping symptoms between substance use and dysthymia, a precise diagnosis and treatment plan may be difficult to achieve as a result.

Prognosis

The prognosis and progression of dysthymia have been positively impacted by antidepressants as well as treatments such as cognitive and behavioral therapies.  One year following a dysthymia diagnosis, 10–15% of patients have remission, and 25% may never fully recover.
The prognosis for dysthymia is often good with appropriate therapy, highlighting the significance of early identification and management to improve results.

Dysthymic Variants

Dysthymia may coexist in older people with physically incapacitating chronic conditions, potentially making the illness worse.  Dysthymia treatment is important because it may influence how the physical ailment progresses.  In neurological disorders such as stroke, individuals may present with a clinical picture resembling dysthymia, marked by subthreshold depressed symptoms that last for more than six months. 
In some situations, treating dysthymia may have an impact on how the related neurological disorder develops.  Dysthymia in children may escalate to major depressive episodes and have an episodic pattern with remissions and exacerbations.  After reaching puberty, about 15-20% of these kids may experience mixed, hypomanic, or mania episodes and may receive a bipolar disorder diagnosis.
A persistent unipolar course with sporadic major depressive episodes may be seen in individuals with dysthymia.  Antidepressant treatment may cause hypomanic symptoms, particularly when there is a positive family history of bipolar illness, suggesting a possible connection between bipolar disorder and major depressive disorder (MDD).

Subsyndromal Symptoms

In clinical settings, dysthymia patients may exhibit subsyndromal symptoms, highlighting the spectrum nature of mood disorders and the difficulty in making an appropriate diagnosis.

Course Of Mdd

1. Recurrent Major Depressive Disorder

Individuals undergo discrete episodes of profound depression interspersed with periods of well-being.  Among the courses mentioned, thought to have the best future outlook.

2. Partial Remission Between Episodes

 Patients show signs of partial remission throughout the inter-episode time, but they still experience significant depressive episodes without having previously had dysthymia.Dysthymia-like symptoms may appear in between two major depressive episodes.

3. Inter-Episodic Recovery Followed by Recurrence

Depressive episodes are characterized by antecedent dysthymia that precedes them, complete recovery taking place in between, and a subsequent depressive episode.  Seldom seen, making up less than 3% of patients suffering from major depression.  Uncommon Pattern: Presentations in MDD patients are noticeably less frequent. 

4. Double Depression

 Accompanied by dysthymia and a depressed episode, with no total remission occurring in between the episodes.  Referred to as "double depression," this term describes how symptoms continue to exist between episodes.

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