Depression

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Depression\: mood disorder with persistent low mood, low energy, anhedonia; can be unipolar or bipolar.
Aetiology\: multifactorial; includes biological (family history, female sex), psychological (personality traits, trauma), social
(lack of support, low socioeconomic status) factors.
Risk factors\: genetics, personality traits, physical illness, substance misuse, lack of social support, low socioeconomic
status, marital status (separated/divorced).
Core symptoms\: low mood, anhedonia, lack of energy; other symptoms include weight change, disturbed sleep,
psychomotor changes, reduced libido, guilt, concentration issues, suicidal thoughts.
Somatic symptoms\: anhedonia, loss of emotional reactivity, diurnal mood changes, early morning wakening, psychomotor
changes, appetite loss, weight loss.
Psychotic symptoms\: delusions (guilt, inadequacy), hallucinations (auditory, olfactory, visual); mood-congruent.
Diagnosis\: based on ICD-10/11 criteria; mild (2 typical core symptoms + 2 other core symptoms), moderate (2 typical core
symptoms + 3 other core symptoms), severe (3 core + 4 other core symptoms).
Investigations\: FBC, thyroid function tests, vitamin B12 levels; screening tools like PHQ-9.
Management\: bio-psycho-social approach; mild (psychosocial interventions), moderate/severe (CBT, antidepressants),
severe (ECT if needed).
Complications\: suicide, substance misuse, persistent symptoms, recurrence, reduced quality of life, antidepressant side
e
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A comprehensive topic overview

Introduction

Depression is a mood (a
interest/enjoyment in everyday activities (anhedonia).
1,2
It can be unipolar (
The onset of individual episodes is often related to stressful events or situations, and it usually runs a relapsing and
remitting course.
Depression is common, with the prevalence in the United Kingdom estimated to be approximately 4.5%.Figure 1. The categorisation of depression

Aetiology

In depression, aetiology is multifactorial with a combination of risk factors from biological, psychological and social
categories. These factors can be predisposing, precipitating or perpetuating.
Table 1. An overview of the risk factors for depression.
Predisposing
Biological Psychological Social
Family history of
depression and
anxiety
Age (teenage
years to early
40s)
Female sex
Personality traits
Childhood
trauma
Lack of social
support
Poor
socioeconomic
status
Marital status-
separated/divorced
Precipitating
(trigger)
Comorbid
substance
misuse
Physical health
problems
Traumatic life
events
Low self-esteem
Lack of social
support
Poor
socioeconomic
status
Marital status-
separated/divorced
Perpetuating
(maintaining)
Comorbid
substance
misuse
Physical health
problems
Failure to cope
with loss
Ongoing loss
Lack of social
support
Poor
socioeconomic
status
Protective factors must also be considered including\:
Current employment
Good social support
Marital status\: being married

Risk factors

There is often not a single identi
chances of developing the illness.Biological factors
Biological factors which increase the risk of depression include\:
Genetics\: family history of depression in the nuclear family increases the risk to almost 30-40% and up to 50% in
monozygotic twins
Personality\: dependent, anxious, impulsivity and obsessional traits
Physical illness\: neurological illnesses such as Parkinson’s disease and multiple sclerosis, hypothyroidism or chronic
illnesses
Biochemical theories/monoamine de
Neuroendocrine\: hypothalamic-pituitary-adrenal axis
Co-morbid substance misuse
Medications\: beta-blockers, steroids
History of other mental illnesses\: anxiety
Psychological factors
Psychological factors which increase the risk of depression include\:
Traumatic life events/childhood experiences\: adverse experiences including loss of a loved one, lack of parental care
and childhood sexual abuse
Environmental factors (e.g. support)
Low self-esteem and negative automated thoughts (e.g. helplessness, hopelessness, worthlessness)
Lack of education
Social factors
Social factors which increase the risk of depression include\:
Poor social support
Poor economic status or support
Marital status\: separated or divorced

Clinical features

A diagnosis of a depressive episode (following ICD-10/ICD-11 criteria) requires the following\:
The presence of symptoms for at least 2 weeks (this may be less if depression is severe)
The symptoms are not attributable to other organic or substance causes (e.g. normal bereavement)
The symptoms impair daily function and cause signi
For more information, see the Geeky Medics guide to depression history taking.
Core symptoms
The three typical core symptoms of depression include\:
Low mood
Anhedonia\: low interest or pleasure in most activities of the day
Lack of energy (anergia)
Other core symptoms of depression include\:
Weight change\: exclusion of intentional dieting
Disturbed sleep\: insomnia or hypersomnia
Psychomotor retardation (slowed down actions) or psychomotor agitation (increased restlessness)
Reduced libido
Worthlessness or guilt feelings
Decreased concentration
Recurring thoughts of harm, death or suicide\: nihilistic thoughts
Somatic/biological symptomsSomatic symptoms of depression (also often referred to as the biological symptoms of depression) may include\:
Anhedonia
Loss of emotional reactivity
Diurnal mood changes\: mood often worse in the morning
Early morning wakening\: typically 2-3 hours earlier than usual
Psychomotor retardation or psychomotor agitation
Appetite loss
Weight loss
Psychotic symptoms
Psychotic symptoms of depression (if present, these are usually mood-congruent) may include\:
Delusions\: often revolving around guilt and personal inadequacy
Hallucinations\: can be auditory, olfactory or visual
Mood-incongruent (delusions/hallucinations that are not consistent with typical depressive themes), including more
rank symptoms (e.g. thought insertion), are often associated with other psychiatric illnesses such as schizophrenia.
Risk assessment
It is important to conduct a risk assessment, including\:
Risk to self\: self-harm, suicide or neglect (commonest in depression)
Risk to others\: when depression presents with psychotic features, such as command hallucinations, they may be at risk
of harming others
Risk from others\: patients with depressive symptoms may be more vulnerable to abuse, criminal acts or neglect
For more information, see the Geeky Medics guide to suicide risk assessment.

Di

Symptoms of depression may be present in other psychiatric illnesses and physical health illnesses, often endocrine or
nutritional in aetiology.
Psychiatric di
Depressive episode linked to substance/medication use\: this by de
criteria for a depressive episode.
Bipolar a\: depressive episodes are interspersed with one or more manic/hypomanic episodes.
Diagnosed using ICD-10/11 criteria for bipolar a
Premenstrual dysphoric disorder\: symptoms occur the week before menses and resolve when menses starts.
Diagnosed using ICD-10/11 criteria for premenstrual dysphoric disorder.
Bereavement\: depressive symptoms often present transiently in normal grief. Diagnosed using ICD-10/11 criteria for
bereavement.
Anxiety disorders\: can frequently co-present with depressive episodes. Diagnosed using ICD-10/11 criteria for anxiety
illnesses.
Alcohol-use disorder\: patients often describe sleep and concentration symptoms. Screened for with the CAGE or AUDIT
questionnaires.
Physical health illness or organic illness di
Hypothyroidism\: patients often have weight and appetite changes. Diagnosis is conelevated thyroid
stimulating hormone (TSH) blood result.
Cushing’s disease or syndrome\: physical signs such as obesity and proximal muscle wasting are often present\:
Diagnosis is con
Vitamin B12 de
paraesthesia and impaired memory. Diagnosis is made conInvestigations
The diagnosis of a depressive episode is clinical according to the ICD-10/11 diagnostic criteria.
Screening questionnaires such as the patient-health-questionnaire-9 (PHQ-9) can be used to screen for symptoms of a
depressive episode.
Investigations may be considered to exclude physical/organic causes of the patient's symptoms. These may include\:
Full blood count\: anaemia
Thyroid function test\: hypothyroidism (elevated thyroid stimulating hormone)
Vitamin B12\: vitamin b12 de
Imaging and other investigations (e.g. a CT head) may be performed in patients with atypical features and signs indicative
of an organic pathology (e.g. low mood associated with a sudden loss of memory and change in personality).

Diagnosis

Depression is graded, following the ICD-11 criteria, as mild, moderate or severe\:
Mild depression requires two typical core symptoms plus two other core symptoms
Moderate depression requires two typical core symptoms plus at least three other core symptoms
Severe depression requires all three typical core symptoms plus at least four other core symptoms.
ICD-11 further classi
1. Mild depressive episode, with or without somatic symptoms
2. Moderate depressive episode, with or without somatic symptoms
3. Severe depressive episode, with or without psychotic symptoms\: these may be mood-congruent or incongruent psychotic
symptoms
4. Recurrent depressive disorder\: when one has two more depressive episodes

Management

Management is based on the bio-psycho-social model and is divided into short-term and long-term strategies.
3
Management is dependent on symptoms the individual has (e.g. di
It is important to educate patients about the disease and provide both written and verbal information to patients. The Royal
College of Psychiatrists has produced a patient information lea.
Mild depression
Short-term management
First-line management should involve initiating primarily low-intensity psychosocial interventions.
In the United Kingdom, the 2022 NICE guidelines recommend the following interventions, based on implementation,
clinical and cost-e
3
Guided self-help
Group cognitive-behavioural therapy (CBT)
Group behavioural activation
Individual CBT
Group behavioural activation
Structured group physical activity programme
Group mindfulness and mediation
Interpersonal psychotherapy
Selective serotonin reuptake inhibitor (SSRI) antidepressantsCounselling
Short-term psychodynamic psychotherapy
Antidepressants should not be routinely o
starting on biological therapy (i.e. antidepressants) include\:
Past history of moderate or severe depression
Presence of mild depression that has been present for at least 2 years
Presence of mild depressive symptoms after other interventions
Long-term management
Longer-term management of mild depression includes\:
Risk assessment
Ongoing review\: response to low-intensity psychosocial intervention, compliance and symptoms. An SSRI
antidepressant should provide bene
Measurement scales to assess response to treatment and quality of life
Relapse prevention plan
Assess for social support, and review previous issues
If taking antidepressant therapy review compliance, side e
Moderate or severe depression
Short-term management
First-line management involves a number of treatment options, which may include a combination of antidepressant
therapy (biological treatment) and high-intensity psychosocial interventions.
In the United Kingdom, the 2022 NICE guidelines recommend the following interventions in descending order, based on
implementation, clinical and cost-e
3
Combination of individual CBT and an antidepressant (e.g. SSRI)
Individual CBT
Individual behavioural activation
Antidepressants (e.g. SSRI) alone
Individual problem-solving
Counselling
Short-term psychodynamic psychotherapy
Interpersonal psychotherapy
Guided self-help
Group exercise
If they are presenting with a severe depressive episode with psychotic symptoms, then treatment should be augmented
with an antipsychotic (quetiapine or olanzapine).
Electroconvulsive therapy (ECT) should be considered in severe cases of depression where\:
The patient has a strong preference for ECT\: this usually applies when patients have responded to ECT well before
Rapid treatment of the patient is needed\: cases of life-threatening depression where the patient is not eating or drinking
Multiple other treatments have been trialled unsuccessfully
Long-term management
Long-term management of moderate or severe depression includes\:
Risk assessment
Review their response to high-intensity psychosocial intervention compliance and symptoms
Review their response to antidepressant therapy, compliance, side e
Measurement scales to assess response to treatment and quality of life
Relapse prevention plan
Assess social support and previous issues Complications
Complications of depression include\:
3
Suicide\: the risk of suicide in patients with depression is four times higher than in patients without depression
Substance misuse and alcohol use problems\: patients are at increased risk of becoming dependent on substances
Persistent symptoms\: 10-20% of patients will have persistent symptoms over 2 years
Recurrence of depressive episodes\: most patients have a recurrence in later life
Reduced quality of life\: patients may struggle with employment and relationships
Antidepressant side e

References

Greg Lydall, M.D., Noreen Jakeman, Sheena Webb (2009) 'A
, in Sarah Stringer, L.C., Susan Davison,
Maurice Lipsedge (ed.) P s y c h i a t r y P .R .N . Oxford University Press
International Classi
Available from\: [LINK]
National Institute for Health and Care Excellence (2022). Depression in adults\: treatment and management (update).
Available from\: [LINK]

Reviewer

Related notes

Dr Nusrat Khan
Anxiety Disorders
Clinical Associate Professor and Consultant Psychiatrist
Bipolar Disorder
Newcastle University
Bulimia Nervosa
Dr Kimberly Kendall
Medically Unexplained Symptoms
ST5 General Adult Psychiatry
Personality Disorder

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Contents

Introduction
Aetiology
Risk factors
Clinical features
Di
Investigations
Diagnosis
Source\: geekymedics.com