🔑 Key Learning
- Depression is diagnosed if ≥5 symptoms persist for ≥2 weeks, including low mood or anhedonia
- Severity is classified using symptom count or the PHQ-9 score
- Management is stepped, based on severity and patient preference, with CBT and SSRIs as first-line treatments
- Fluoxetine is preferred in children; sertraline is safest in comorbid physical illness
📋 Diagnosis of Depression (DSM-5)
A diagnosis of major depressive disorder requires 5 or more of the following symptoms for ≥2 weeks, including either depressed mood or anhedonia:
- Depressed mood most of the time
- Anhedonia – loss of interest or pleasure
- Weight change (loss or gain)
- Psychomotor retardation (slow movement/thought)
- Fatigue
- Feelings of worthlessness or guilt
- Poor concentration or indecisiveness
- Recurrent thoughts of death or suicidal ideation
- Sleep disturbance (insomnia or hypersomnia)
- Appetite changes
- Irritability
Classification by symptom count
- <5 symptoms = Subthreshold
- 5–6 symptoms with mild functional impairment = Mild
- Moderate = Intermediate severity
- Severe = Most symptoms + marked functional impairment
🧪 Assessment Tools
PHQ-9
- 9 questions, each scored 0–3
- Score < 16 → less severe depression
- Score ≥ 16 → moderate or severe depression
- Used to guide diagnosis and monitor progress
💊 Management of Depression (NICE CKS 2024)
Less severe depression
No treatment requested / symptoms improving
- Active monitoring
- Review in 2–4 weeks
Wants treatment
- First-line: Guided self-help (CBT-based)
- Do not routinely offer antidepressants
- If patient prefers medication: consider SSRI
More severe depression
Offer one of the following based on patient preference:
- CBT (individual)
- Behavioural activation therapy
- Group exercise
- Antidepressants (SSRI or SNRI)
Review all patients in 2–4 weeks after starting treatment
💊 Choosing an Antidepressant
First-line: SSRIs
- Sertraline or citalopram preferred for tolerability
- Citalopram – may prolong QTc (consider ECG if cardiac risk)
- Sertraline – safer in patients with ischaemic heart disease, or patients on multiple drugs (few interactions)
- Fluoxetine – preferred in children and adolescents
👵 Depression in the Elderly
Clinical features
- Atypical presentation – may lack low mood
- Agitation, insomnia, somatic symptoms (e.g. weight loss)
- Often present with memory concerns (global memory loss)
Management
- First-line: SSRI
⚡ Electroconvulsive Therapy (ECT)
Used in severe, treatment-resistant depression
Contraindication
- Raised intracranial pressure
Adverse effects
- Short-term: headache, memory loss, arrhythmia
- Long-term: persistent memory impairment
❄️ Seasonal Affective Disorder (SAD)
Description
- Recurrent depressive symptoms during winter months
Management
- Same as typical depression: CBT, SSRIs as needed
⚠️ Suicide Risk Stratification
Risk factors for suicide include:
- Male sex
- History of self-harm or suicide attempt
- Alcohol or drug misuse
- Pre-existing mental illness
- Chronic physical illness
- Increasing age
- Unemployment
- Social isolation or loneliness
- Living alone
- Single, widowed, or divorced
📝 Exam Clues & Clinchers
- ≥5 symptoms for ≥2 weeks including low mood or anhedonia → think depression
- Elderly patient with weight loss, agitation and memory concerns → consider depression, not just dementia
- PHQ-9 score ≥16 → treat as moderate to severe
- First-line pharmacological treatment → SSRI (sertraline or citalopram)
- Patient with IHD or polypharmacy → sertraline is safest
- Patient prefers non-drug treatment → guided CBT or behavioural activation
- Atypical symptoms + memory loss → think depression in elderly
- Fluoxetine is safest in young people