Bipolar Disorder

The cause is unknown, however, there are thought to be a number of contributing factors including psychosocial stressors, a strong hereditary component, imbalances in neurotransmitters such as serotonin, noradrenaline, and dopamine, and nutritional deficiencies.

Bipolar Disorder I

This is the true, severe form of bipolar disorder, defined by one or more full manic episodes that are often accompanied by major depressive episodes.

Bipolar Disorder II

This classification involves milder hypomanic episodes rather than full mania, combined with one or more major depressive episodes. The depressive component tends to dominate.

Unspecified Bipolar Disorder

This category covers presentations with clear bipolar features that do not meet the full criteria for bipolar I or bipolar II disorder.

Manic episodes feature elevated or irritable mood, inflated self-esteem or grandiosity, reduced need for sleep, rapid or pressured speech, racing thoughts, distractibility, and impulsive or risk-taking behavior. Depressive episodes feature low mood, loss of interest or pleasure, fatigue, changes in appetite and sleep, poor concentration, feelings of worthlessness, and thoughts of death or suicide.

Diagnosis is clinical and based on a detailed history of mood episodes, their duration, and their impact on functioning. The distinction between mania and hypomania, and the presence of psychotic features, guides classification. Investigations are used mainly to exclude organic and substance-related causes.

Bipolar disorder commonly co-occurs with anxiety disorders, substance use disorders, and attention deficit hyperactivity disorder. There is also an increased risk of metabolic conditions such as obesity and type 2 diabetes, partly related to medication effects and lifestyle factors.