What is Bipolar Disorder?
It is a mental health condition which presents with mood symptoms, which can swing quite quickly from one extreme, depression (very low mood) to mania (very high mood), vice versa. Some individuals suffering from this condition, have described this sudden change, like a switch.

How common is it?
The incidence in the general population is about 1%. This increases significantly in an individual who has a family member suffering from bipolar disorder. The incidence of clinical depression also increases.

What causes it?
There are genetic, and environmental factors which may make an individual vulnerable to developing bipolar disorder. However, in common with other mental health conditions, the exact cause is unknown.

Genetic factors
The incidence of bipolar disorder in an individual, is significantly increased if a close family member suffers from the condition, shown by identical twin studies. Multiple, rather than a single gene, are involved.

Environmental factors
Traumatic events in childhood like sexual abuse, may make an individual more vulnerable to developing bipolar disorder later on in life.

Possible triggers

• Very stressful or loss (losing a loved one) events, may also trigger depression
• Physical illness (can also trigger clinical depression)
• Lack of sleep
• Certain medicines, like steroids

What are the symptoms?
Depression alternating with mania, with normal mood in between at times. Diagnosis is by clinical assessment. Use of a mood scale (like the one used by “Bipolar UK”), is essential in establishing mood changes and response to treatment.
(See diagram below)

Mood changes in Bipolar disorder

Depression

• Persistent low mood
• Loss of interest/enjoyment
• Reduced appetite/weight changes
• Poor sleep/excessive sleep
• Poor concentration/short term memory
• Worthless feelings
• Thoughts of suicide

Mania/hypomania

• Elevated/expansive or irritable mood
• Increased energy
• Impulsive behaviours like excessive spending
• Talking too fast
•  Racing thoughts
• Increased sexual drive
• Decreased need for sleep
• Abnormal beliefs (delusions), seeing or hearing things (hallucinations), in mania

Mixed episode
Both symptoms of depression, and mania are present at the same time, like having racing thoughts, and feeling depressed.

Rapid cycling
Mood changes very rapidly between depression, and mania with no periods in between of normal mood. This can be very frequent within hours or days.

What is the difference between bipolar 1 and 2 disorders?

Bipolar 1: Individuals present mainly with manic (severe form of hypomania).

Bipolar 2: Individuals present with prolonged episodes of depression alternating with hypomania (less severe form mania).

What are the possible changes in the brain?
Three main chemicals: (monoamine neurotransmitters)

• Serotonin (ST)
• Noradrenaline/Norepinephrine (NA/NE)
• Dopamine (DA)

Control symptoms/behaviours in different emotional (limbic) brain areas like

• Prefrontal cortex (PFC)
• Amygdala (M)
• Hippocampus (H)

Normal mood state
Chemicals are in the middle

Depression
Chemicals low

Mania
Chemicals high (see diagram above)

Mania is said to be the opposite of depression. There is possibly a switch in the emotional (limbic) brain which control these chemicals, and when it is malfunctioning these chemicals (neurotransmitters) are in excess (mania) or low (depression). These chemicals (ST, NA, DA), carry messages (symptoms/behaviours of depression and mania) in between different parts of the emotional brain through electrical activity created in the nerve cells (neurons).

Thus, there is electrical activity in the emotional brain similar to the one which occurs in someone having a seizure in epilepsy, and hence that’s why medicines for epilepsy like Lamotrigine are effective in bipolar disorder. Lamotrigine, and similar medicines damp down this electrical activity in the emotional brain, and by doing this, control symptoms of bipolar disorder.

What is the available treatment?

• Medicines
• Psychological
• Life style changes

Medicines
Balance the chemicals (neurotransmitters, ST, NA, DA) either directly or indirectly.

Four types used:

1. Antidepressants
2. Lithium
3. Antiepileptic mood stabilisers (should be avoided in pregnancy)
4. Antipsychotics Old (typical) New (atypical)

Antidepressants
Individuals presenting with depression (bipolar depression) are likely to be treated with antidepressants by their GP. However, on their own, are unlikely to be effective as they may cause rapid fluctuations of mood especially strong antidepressants like Venlafaxine or Mirtazapine. If they are used, should combined with mood stabilisers.

Lithium
Used for treatment of both depression, and mania.
It is a salt which has effect on brain cells (neurons) to balance/modify brain chemicals (neurotransmitters). It increases the chemical GABA (Gamma Aminobutyric acid), and reduces glutamate. (GABA is a dampening/inhibitory chemical/neurotransmitter. Glutamate is an enhancing/excitatory chemical/neurotransmitter, which does the opposite of GABA. Both GABA, and glutamate nerve cells/neurons are connected to ST, NA, and DA cells/neurons, and can influence their actions, and hence control their levels). Regular lithium blood levels, and tests every 3 months need to be checked to avoid side effects due to high lithium level, and effect on the thyroid gland, and kidneys.

Antiepileptic mood stabiliser

• Valproic acid
• Carbamazepine
• Lamotrigine
• Topiramate

Valproic acid (Epilim, Depakote)

• Enhances GABA, and reduces glutamate
• Effective especially for mania
• It should be avoided for women of child bearing age, risk of the baby developing spina bifida, and heart abnormalities
• Other side effects include weight gain, and hair loss

Carbamazepine

• Enhances GABA
• May interfere with blood levels (increasing or lowering it) of other prescribed medication, and may lower white blood cells

Lamotrigine

• Reduces effects of glutamate
• Effective in bipolar depression on its own or with SSRI’s (Serotonin Reuptake Inhibitors) like Prozac/Fluoxetine, Sertraline etc (I find it beneficial in this group of patients)
• 10% of patients may develop a rash, and should be stopped immediately
  May affect contraceptive pill. If possible, to be avoided in pregnant individuals

Topiramate

• Increases GABA, and reduces glutamate. (In my experience it is more effective in mania, and may stabilise an individual at lower level, needing to add antidepressants)
• Has an important action on the reward centre by reducing craving, especially stimulants like cocaine (I find useful for treating patients with bipolar disorder who also abuse substances). One useful side effect is weight loss. (Most of my patients like this side effect!) Kidney stones is a rare side effect, so individuals should be advised to drink adequate fluids

Antipsychotics

• New (atypical) include Quetiapine, Olanzapine, Aripiprazole, at low doses, they work as antidepressants (effect on the serotonin system)
• Old (typical); the common one used now is Haloperidol, this may be used for mania, and related psychosis (its effect of blocking the dopamine system)

Psychological
This is would be beneficial in addition to medication

• Psychoeducation
• Cognitive behavioural therapy (CBT)

Life style changes

• Exercise (chasing dopamine), beneficial in bipolar depression. (Some of my patients have reported worsening of their manic symptoms if they exercise; likely due to increase of dopamine)
• Balanced diet
• Omega 3 fatty acids with EPA 2 to 3 g per day has been shown to be beneficial
  Sleep hygiene, in order to have good quality sleep

 

Further reading on the subject

• My Brian Is Out of Control – Dr Patrick Mbaya
• NHS website
• Bipolar UK website
• Shorter Text book of Psychiatry, seventh Edition, Oxford University
• Stahl’s Essential Psychopharmacology, Fourth Edition

 

The views in this article, are my own, based on my knowledge, clinical experience as a psychiatrist, treating people with mood disorders over the years.
Dr Patrick Mbaya MD FRCPsych.