Chronic episodic illness associated with behavioural disturbances; patients suffer bouts of both depression and mania
Aetiology
Onset usually late teens/early 20s
A family history of BPAD often early results in earlier onset and episodes are precipitated by lower levels of stress
There is often a delay between first presentation and diagnosis
Onset after the age of 60 is rare and is often associated with treatment-resistance, progressive decline in functioning, and an underlying organic cause
High comorbidity with other psychiatric disorders (anxiety disorders, substance misuse, personality disorders, eating disorders, schizoaffective disorder, schizophrenia)
Clinical features
Bipolar subtypes
Bipolar I: this type presents with manic episodes (most commonly interspersed with major depressive episodes)
The manic episodes are severe and result in impaired functioning and frequent hospital admissions
Bipolar II: patients do not meet the criteria for full mania and are described as hypomanic
This type is often interspersed with depressive episodes
Represents the most common form of illness
ICD-11 hypomanic episode
The mood is elevated or irritable to a degree that is definitely abnormal for the individual concerned and sustained for at least 4 consecutive days
At least 3 of the following signs must be present, leading to some interference with personal functioning in daily living
Increased activity or physical restlessness
Increased talkativeness
Difficulty in concentration or distractibility
Decreased need for sleep
Increased sexual energy
Mild spending sprees, or other types of reckless or irresponsible behaviour
Hypomania in comparison to mania has no psychotic symptoms and results in less associated dysfunction
ICD-11 manic episode
Mood must be predominantly elevated, expansive or irritable, and definitely abnormal for the individual concerned
The mood change must be prominent and sustained for at least 1 week (unless it is severe enough to require hospital admission)
At least 3 of the following signs must be present (4 if the mood is merely irritable), leading to severe interference with personal functioning in daily living
Increased activity or physical restlessness
Increased talkativeness ('pressure of speech')
Flight of ideas or the subjective experience of thoughts racing
Loss of normal social inhibitions resulting in behaviour which is inappropriate to the circumstances
Decreased need for sleep
Inflated self-esteem or grandiosity
Distractibility or constant changes in activity or plans
Behaviour which is foolhardy or reckless and whose risks the subject does not recognise e.g. spending sprees, reckless driving