4: Characteristics of Affective Disorders

Depression

Affects 15-20% of patient pop at any given time, not counting reactive depression

• loss of interest, anhedonia (inability to experience pleasure), guilt, sadness, suicide (7-15%)

• Typically preceded by an anxiety disorder

• 6-10 months with episodes for life

Bipolar

Cycles of depression and mania affecting about 1% of pop

Manic episode symptoms

Flight of ideas, distractedness, euphoria

Are affective disorders genetic?

Genes are 1 part of the picture

65% will have one if their identical twin does, 20% if their fraternal twin does

• We have not found specific affective gene

Describe the HPA axis

Central nucleus of the amygdala stimulates the hypothalamus to release corticotropin releasing hormone to anterior pituitary which then releases adrenalcorticontropie hormone on adrenal cortex which then releases cortisol into the bloodstream

What happens to cortisol and CRF level with early life trauma

Early life trauma increases cortisol levels and then increases CRF

Do antidepressants target NTs or hormones

NTs, but can decrease CRF, except sometimes this effect reverses when the drug is stopped

Sleep in bipolar vs in depression

Depression: Less REM and sleep onset decreases, less restoring sleep. Melatonin is not that helpful

Manic episodes of bipolar: Have very little sleep