20th November 2023

Depressive Disorders

Depression is defined as a disorder of depressed mood, but as highlighted below, a patient need not have this typical symptom to be suffering from this condition. It is, unfortunately, very common, affecting roughly 1 in 6 adults experiencing it in the United Kingdom. To meet the criteria for a clinical depressive episode (ICD-11), the patient must experience at least two of the following. (These are sometimes referred to as the core symptoms.)

• Depressed mood for most of the time, almost every day for two weeks.
• Loss of interest or pleasure in activities (also known as anhedonia).
• Decreased energy or increased fatigue (anergia).

The patient must then also have additional symptoms from the list below. It is the total number of symptoms the patient is experiencing (including either the two or three above) that determine the severity of the disorder.

• Loss of confidence or self esteem.
• Unreasonable feelings of self-reproach (blaming yourself) or excessive and inappropriate guilt.
• Recurrent thoughts of death or suicide or any suicidal behaviour.
• Difficulty in concentrating or thinking.
• Changes in psychomotor activity (agitated or slowing down): these can be observed or self reported.
• Trouble with sleep.
• Increased or decreased appetite with associated weight change.

Types of depressive episode

• Mild depressive episode – Total of 4 symptoms (including at least 2 core symptoms).
• Moderate depressive episode – Total of 6 symptoms (including at least 2 core symptoms).
• Severe depressive episode – Total of 8 symptoms (including all 3 core symptoms).

As above, depression can be classified into a mild, moderate or severe episode. It can then also be further classified as to whether it is a recurrent disorder or a single episode and whether there is the presence of psychotic symptoms.

Differences in the DSM V

The DSM V criteria for major depressive disorder are broadly similar. They use two core symptoms of depressed mood or anhedonia, of which the patient must have one of. The patient must also have 5 symptoms in total. The DSM-V does not recognise loss of confidence and self esteem as a separate criteria. It also states that the agitation or slowing down of activity must be ‘observable by others’ and not just described subjectively by the patient.

Persistent mood disorders

There are two persistent mood disorders referred to as cyclothymia and dysthymia. These disorders should only be considered if you are confident the patient is not experiencing the disorders above. The symptoms must have been present for at least two years:

Cyclothymia – Unstable mood with episodes of both depressed mood and hypomania. However, none of these episodes should be severe enough to meet the criteria for mania or depression.

Dysthymia – A depressed mood that is present nearly all of the time. There may be intermittent periods of normal mood, but these should not last more than a couple of weeks. The individual episodes of depressed mood should not be severe enough to meet the criteria for depression.

Psychotic symptoms in mood disorders

Patients with depression and bipolar disorder can experience psychotic symptoms in relation to their mood disorder. These are delusions and hallucinations that are not listed under the criteria for a schizophrenic diagnosis. In episodes of depression, examples could be persecutory or nihilistic hallucinations or delusions. The patient could also be suffering from a ‘depressive stupor’ and appear catatonic. In episodes of mania, the patient may be experiencing grandiose delusions or hallucinations.

References

• World Health Organization. (‎2004)‎. ICD-10 : international statistical classification of diseases and related health problems : tenth revision, 2nd ed. World Health Organization. https://apps.who.int/iris/handle/10665/42980
• International Classification of Diseases, Eleventh Revision (ICD-11), World Health Organization (WHO) 2019/2021 https://icd.who.int/browse11. Licensed under Creative Commons Attribution-NoDerivatives 3.0 IGO licence (CC BY-ND 3.0 IGO)
• American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). https://doi.org/10.1176/appi.books.9780890425596
• Cullum Attwell, R.M. (2022) Cost of living and depression in adults, Great Britain: 29 September to 23 October 2022, Cost of living and depression in adults, Great Britain – Office for National Statistics. Office for National Statistics. Available online at: https://www.ons.gov.uk/peoplepopulationandcommunity/healthandsocialcare/mentalhealth/articles/costoflivinganddepressioninadultsgreatbritain/29septemberto23october2022 [Accessed: March 26 2023]