Bipolar Disorder Definition Characterised by alternating episodes of mania or hypomania and major depression interspersed with periods of normal mood and functioning. Types Bipolar I Disorder • • • • • At least one manic episode has occurred Major depressive or hypomanic episodes but not required for diagnosis. If manic symptoms have led to hospitalisation or if there re psychotic symptoms Usually accompanied by at least 1 MDE, but not required for diagnosis time spent in mood episodes: 53% asymptomatic, 32% depressed, 9% cycling/mixed, 6% hypo/manic Bipolar II Disorder • • • • • • there is at least 1 MDE hypomanic episode and no manic episodes at least one episode of hypomania and one major depressive episode, no previous episodes of mania - DISTTINGUSHING FEATURE FROM BIPOLAR I hypomania is less severe than mania NOT a milder form of bipolar I time spent in mood episodes: 46% asymptomatic, 50% depressed, 1% cycling/mixed, 2% hypo/ manic often missed due to severity and chronicity of depressive episodes and low rates of spontaneous reporting and recognising of hypomanic episodes. Epidemiology • • • • Men and woman are equally affected Average age of onset is 20. Frequency increases with age Lifetime prevalence: - 1 – 3 % of general population - First degree relative with bipolar disorder -> up to 10%. - Monozygotic twin -> 40 to 70%. Aetiology • • Multifactorial origin: - Strong genetic component - Increase parental age -> increase in mutations in spermatogenesis -> increase the risk of bipolar disorder in offspring. Triggers - Psychological stress - Medications ➔E.g. dexamethasone - Childhood traumatic experiences - Sleep disturbances - Physical illness Clinical Features • • • Manic/hypomanic episodes - Characterised by elevated mood - Intense sense of happiness e.g. for several days - Irritability - Overconfidence and risk behaviour ➔E.g. overspending money - Decreased need for sleep - Hypersexuality - Psychotic features ➔Only in manic episodes Major depressive episode - Characterised by depressive mood - Anhedonia - Fatigue - Sleep disturbances - Frequent reports of pain e.g. headache, stomach pain etc. - Lack of interest in activities previously enjoyed - Feelings of worthlessness of guilt - Suicidal ideation. Features in children - Changes during manic episodic: - ➔Sleeping only for a few hours without feeling tired ➔Difficulty staying focused in school ➔Increased interest in risky behaviour Changes during depressive episodes: ➔Sleeping more than usual e.g. more than 12 hours several days in a row. ➔Lack of interest in activities previously enjoyed. ➔Feelings of doing everything wrong. Subtypes Rapid cycling • Patients with rapid cycling with 4 or more episodes of depression, mania, hypomania occurring in a single year. Cyclothymia • • • Instability of mood involving numerous periods of depressive symptoms and periods of hypomanic symptoms Symptoms not severe enough or persistent enough to diagnosis bipolar disorder - Never meet the criteria for a major depressive or hypomanic episodes Symptoms last at least 2 years and are present for at least half of the time and are never absent for more than 2 months at a time. Substance/medication-induced bipolar and related disorder • Elevated, disinhibited or irritable mood with/without depressed mood or anhedonia that develops during or soon after substance intoxication or withdrawal.