Bipolar Affective Disorder
Summary
Bipolar Affective Disorder (BPAD) is a chronic mood disorder characterised by recurrent episodes of mania/hypomania and depression. It affects approximately 1-2% of the population and typically presents in late adolescence or early adulthood. The disorder is associated with significant morbidity, high suicide risk (20x general population), and social and occupational impairment. Treatment involves mood stabilisers (lithium is gold standard), antipsychotics, and psychological therapies. Lifelong management is usually required.
Key Facts
- Prevalence: 1-2% lifetime risk
- Onset: Peak 15-25 years
- Genetics: 70-80% heritability; 10x risk if first-degree relative
- Suicide Risk: 15-20% attempt; 4-5% completed suicide
- Course: Chronic with recurrent episodes
- Treatment: Lithium (gold standard), valproate, antipsychotics
- Bipolar I vs II: Mania (Type I) vs Hypomania (Type II)
Clinical Pearls
High-Yield Points:
- Never give antidepressant monotherapy in bipolar (risk of manic switch)
- Lithium requires careful monitoring (TFTs, U&Es, levels)
- Valproate is teratogenic - avoid in women of childbearing potential
- Lamotrigine is good for bipolar depression prophylaxis
- Mixed states (mania + depression features) are high suicide risk
- First presentation of "depression" in young person - always consider bipolar
Why This Matters Clinically
Bipolar disorder is often misdiagnosed as unipolar depression, leading to antidepressant monotherapy which can trigger manic episodes and rapid cycling. Correct diagnosis enables appropriate mood stabiliser treatment, reducing morbidity and mortality. Understanding the difference between Type I and Type II affects prognosis and treatment selection.
Prevalence and Incidence
| Metric | Value |
|---|---|
| Lifetime Prevalence | 1-2% |
| Bipolar I | 0.6% |
| Bipolar II | 0.4-1% |
| Male:Female | 1:1 (Type I); Female > Male (Type II) |
| Age of Onset | Mean 20-25 years |
Risk Factors
Genetic (Strongest):
- First-degree relative: 10x risk
- Monozygotic twin: 40-70% concordance
- Polygenic inheritance
Environmental:
- Childhood trauma
- Stressful life events (trigger first episode)
- Substance misuse (cannabis, stimulants)
- Sleep deprivation
Neurobiological Models
Monoamine Dysregulation:
- Mania: Elevated dopamine, noradrenaline activity
- Depression: Reduced serotonin activity
Circadian Rhythm Dysfunction:
- Disrupted sleep-wake cycles
- Abnormal melatonin rhythms
- Sleep deprivation can trigger mania
Mitochondrial Dysfunction:
- Impaired energy metabolism in neurons
- Oxidative stress
Structural Changes:
- Reduced prefrontal cortex volume
- Amygdala hyperactivity
- White matter abnormalities
Kindling Hypothesis
- Each episode makes future episodes more likely
- Progressive loss of external triggers
- Supports early and continuous treatment
Bipolar I vs II
| Feature | Bipolar I | Bipolar II |
|---|---|---|
| Mania | Present (≥7 days) | Absent |
| Hypomania | May occur | Present (≥4 days) |
| Depression | Common | Predominant |
| Psychosis | May occur (mania) | Rare |
| Hospitalisation | Often required (mania) | Less common |
| Suicide Risk | High | Very high |
Mania (Bipolar I Defining Feature)
Duration: ≥7 days (or any duration if hospitalised)
Core Symptoms (DIGFAST):
Severity: Marked impairment, may have psychotic features
Hypomania (Bipolar II Defining Feature)
Duration: ≥4 days
Symptoms: Same as mania but:
Depressive Episodes
Mixed States
Mental State Examination (Manic Phase)
| Domain | Findings |
|---|---|
| Appearance | Disinhibited dress, colourful, unkempt |
| Behaviour | Restless, distractible, intrusive |
| Speech | Pressured, rapid, loud |
| Mood | Elated, irritable, labile |
| Affect | Expansive, infectious, or hostile |
| Thought Form | Flight of ideas, loosening |
| Thought Content | Grandiose delusions, no insight |
| Perception | Hallucinations (congruent) - 50% in severe |
| Cognition | Distractibility, poor attention |
| Insight | Usually impaired |
Risk Assessment
Manic Phase Risks:
- Financial ruin (spending sprees)
- Sexual disinhibition (unprotected sex, STIs)
- Aggression (if irritable mania)
- Dangerous activities (driving recklessly)
Depressive Phase Risks:
- Suicide (highest risk when emerging from or entering depression)
- Self-neglect
Diagnostic Workup
| Investigation | Purpose |
|---|---|
| FBC, U&Es, LFTs | Baseline, exclude organic |
| TFTs | Thyroid dysfunction (also lithium monitoring) |
| Glucose, Lipids | Metabolic baseline |
| Urine Drug Screen | Exclude substance-induced |
| ECG | Baseline (antipsychotics) |
Mood Diary/Rating Scales
- Young Mania Rating Scale (YMRS): Mania severity
- Hamilton Depression Scale (HAMD): Depression severity
- Mood Disorder Questionnaire (MDQ): Screening
Exclude Organic Causes
- Hyperthyroidism (mania-like)
- Corticosteroids, stimulants (drug-induced)
- Brain lesions (rarely)
Bipolar Subtypes
| Type | Features |
|---|---|
| Bipolar I | ≥1 manic episode (± depression) |
| Bipolar II | ≥1 hypomanic + ≥1 major depressive |
| Cyclothymia | Chronic fluctuating mood (hypomanic + depressive symptoms, not meeting full criteria) |
| Rapid Cycling | ≥4 episodes per year |
Episode Specifiers
- With anxious distress
- With mixed features
- With psychotic features (mood-congruent/incongruent)
- With catatonia
- With seasonal pattern
- With peripartum onset
Acute Mania
First-Line:
- Antipsychotic (haloperidol, olanzapine, risperidone, quetiapine, aripiprazole)
- Consider adding benzodiazepine for agitation
Stop:
- Antidepressants (can fuel mania)
Consider:
- Lithium (start if not already on)
- Valproate (rapid loading possible)
Setting:
- Often requires inpatient admission (risk, poor insight)
- Consider MHA if lacks capacity/refuses treatment
Acute Bipolar Depression
First-Line:
- Quetiapine (evidence for bipolar depression)
- Olanzapine + fluoxetine (combination)
- Lurasidone
- Lamotrigine (slow titration, less acute effect)
Avoid:
- Antidepressant monotherapy (risk manic switch)
Maintenance (Long-Term)
| Drug | Features | Monitoring |
|---|---|---|
| Lithium | Gold standard; reduces suicide | Levels q3-6m, TFTs, U&Es, eGFR |
| Valproate | Effective but teratogenic | LFTs, weight, avoid in WOCBP |
| Lamotrigine | Good for depression prevention | Rash (risk of SJS - slow titration) |
| Quetiapine | Both phases | Metabolic |
| Aripiprazole | Maintenance | Weight |
Lithium Monitoring
| Parameter | Frequency |
|---|---|
| Serum Lithium | Weekly until stable, then 3-6 monthly |
| Therapeutic Range | 0.6-0.8 mmol/L (maintenance); 0.8-1.0 (acute) |
| TFTs | 6-monthly |
| U&Es, eGFR | 6-monthly |
| Weight, BMI | At each review |
Lithium Toxicity
Symptoms: Tremor, N&V, diarrhoea, confusion, seizures, arrhythmia
Causes: Dehydration, renal impairment, NSAIDs, ACE-I
Management: IV fluids, dialysis if severe (>2.0 mmol/L or symptomatic)
Psychological Therapy
- Psychoeducation (about illness, triggers, drugs)
- CBT for bipolar
- Family-focused therapy
- Interpersonal and social rhythm therapy (IPSRT)
Lifestyle
- Regular sleep schedule (critical)
- Avoid alcohol and recreational drugs
- Mood diary
- Identify early warning signs of relapse
Acute
| Complication | Context |
|---|---|
| Suicide attempt | Depressive/mixed phase |
| Financial ruin | Manic spending |
| Legal problems | Disinhibition, aggression |
| Relationship breakdown | |
| STIs, unplanned pregnancy | Sexual disinhibition |
Chronic
- Cognitive decline
- Metabolic syndrome (medication-related)
- Cardiovascular disease
- Substance use disorder (40-50% comorbid)
- Anxiety disorders (common comorbid)
Natural History
- Chronic relapsing-remitting course
- Average 8-10 episodes in lifetime
- Inter-episode recovery variable
Prognostic Factors
Poor Prognosis:
- Early onset
- Rapid cycling
- Mixed episodes
- Comorbid substance use
- Poor medication adherence
- Psychotic features
Good Prognosis:
- Later onset
- Few prior episodes
- Good insight
- Good social support
- Lithium responsiveness
Mortality
- 15-20 years reduced life expectancy
- Cardiovascular disease (leading cause)
- Suicide (10-15% lifetime risk in untreated)
Key Guidelines
| Guideline | Organisation | Year |
|---|---|---|
| Bipolar Disorder | NICE CG185 | 2014 (Updated 2023) |
| CANMAT/ISBD | CANMAT | 2018 |
| BAP | British Association for Psychopharmacology | 2016 |
Key Evidence
- BALANCE Trial: Lithium monotherapy superior to valproate for long-term prevention
- STEP-BD: Real-world effectiveness data
- Lithium reduces suicide risk (unique among mood stabilisers)
What is Bipolar Disorder?
Bipolar disorder causes extreme mood swings - from feeling abnormally "high" and energetic (mania) to feeling very low and depressed. These mood episodes are much more intense than normal ups and downs and can last for weeks.
What are the symptoms?
Manic episode:
- Feeling extremely energetic, euphoric, or irritable
- Sleeping very little but feeling full of energy
- Racing thoughts and talking very fast
- Making impulsive decisions (spending money, risky behaviour)
- Feeling invincible or having grand ideas
Depressive episode:
- Same as depression - low mood, no energy, hopelessness
- Difficulty with daily activities
- Thoughts of suicide or self-harm
How is it treated?
- Medications: Mood stabilisers (lithium) help even out mood swings
- Talking therapies: Help you understand triggers and manage the condition
- Lifestyle: Regular sleep, avoiding alcohol, and recognising early warning signs
Treatment is usually lifelong, but many people live full and fulfilling lives with proper management.
When to seek urgent help
- Thoughts of suicide or self-harm
- Making dangerous decisions during a "high" period
- Unable to care for yourself
- Hearing or seeing things others cannot
-
NICE. Bipolar disorder: assessment and management (CG185). 2014 (Updated 2023). nice.org.uk
-
Goodwin GM, et al. Evidence-based guidelines for treating bipolar disorder: Revised third edition recommendations from the British Association for Psychopharmacology. J Psychopharmacol. 2016;30(6):495-553. PMID: 26979387
-
Geddes JR, et al. Lithium plus valproate combination therapy versus monotherapy for relapse prevention in bipolar I disorder (BALANCE). Lancet. 2010;375(9712):385-395. PMID: 20092882
-
Vieta E, et al. Bipolar disorders. Nat Rev Dis Primers. 2018;4:18008. PMID: 29516993
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. It does not replace professional medical judgement.