Mood Disorders

Emotions

Psychiological and psychological responses that:

  • Give us information about a situation

  • Help us communicate with others

  • Motivate us to act

Our physiological (sweating, heart pounding, eyes dilate, etc.) and psychological (“feeling” of fear) response:

  • Tell us this a potentially dangerous situation

  • Communicates our perspective to those around us (e.g. through facial expressions and non-verbal physiology)

  • Have urge to fight-flee-freeze or automatically react

Our physiological (low energy, pain/hollow feeling in chest, difficulty swallowing etc.) and psychological (“feeling” of sadness) response:

  • Tells us this was a significant loss

  • Communicates our perspective to those around us (e.g., through facial expressions and non-verbal physiology) to elicit support

  • Have urges to avoid, ruminate, and slowdown

Mood

  • An affective state over a particular time - broadly positive or negative, and consisting of several similar emotions

  • Over the course of a week, a person in a generally positive mood may experience the emotions of happiness, joy, contentment, irritability , and excitement

Mood Disorders

  • Diagnoses defined by a significant disturbances in mood states over prolonged periods of time

    • Depression- low mood episode makes by significant levels of sadness, lack of energy, guilt and other symptoms

    • Mania- high mood episode marked by feelings of euphoria, frenzied activity, and other symptoms

  • In the DSM-5, this includes two categories of diagnoses:

    • Depressive disorders

    • Bipolar disorders

The depressive disorders

  • Major depressive disorder

  • Persistent depressive disorder

  • Premenstrual dysphoric disorder

Prevalence

  • Annually:

    • ~8% of adults and adolescents

    • ~2% of children

  • Lifetime:

    • ~20%

  • Average age of onset is 19 years old

Major Depressive disorder (MDD)

One or more “depressive episodes” aka 2 weeks or more of:

  • Depressed mood and/or decreased enjoyment or interest in activities

  • At least 3 or 4 of the following:

    • Weight or appetite change

    • Sleeping too much or too little

    • Changes in activity level

    • Fatigue or lethargy

    • Feeling worthless or excessively guilty

    • Difficulty with concentration

    • Suicidal ideation, behaviors, or attempts

Persisten depressive disorder

  • Depressed mood for most of the day, more days than not, for at least 2 years

  • Two or more of the following:

    • Appetite changes

    • Sleep disturbance

    • Low energy or fatigue

    • Low self-esteem

    • Poor concentration

    • Feelings of hopelessness

  • During the 2 years, the person must never have been without symptoms for more than 2 months at a time

Depressive disorders: Etiology

Biological

Brain- structural and functional brain differences; low levels of serotonin and norepinephrine

Hormones- Hypothalamic-pituitary-adrenal (HPA) axis is over-reactive when under stress

  • Too much cortisol released

  • Suppresses immune system

Example (MDD with peripartum onset)- Loss, then gain, in brain tissue

Psychological

Cognitions- Negative, unhelpful thinking style or attitudes

Behavior- Avoidance, low activity level

Social

Negative life events- Death, loss, tragedy, major stressors and transitions

Systemic pressures- Discrimination, and disenfranchisement exacerbate risk and negative life events

Etiology: Cognition

Cognitive Triad (Aaron Beck, MD)

  • Negative view of self

  • Negative view of the world

  • Negative view of the future

Etiology: Behavior

Symptoms of depression can result in a “downward spiral”

  • We feel bad and we stop doing “positive things”. Then we feel worse and we’re even less likely to do “positive things” because they were not reinforced

Etiology: Cognitive-behavioral interaction

  • Learned helplessness: People believe they have no control over environment (reinforcers and punishments)

  • Attribution helplessness theory: Learned helplessness is due to global, negative attributions (the cognitive triad)

Part 2

The bipolar disorders

  • Bipolar I

  • Bipolar II

  • Cyclothymic disorder

Mania

Dramatic and inappropriate rise in mood + abnormal need for activity or excitement

+3 or more of the following:

  • Inflated self-esteem or grandiosity

  • Decreased need for sleep

  • More talkative

  • Flight of ideas or racing thoughts

  • Distractibility

  • Psychomotor agitation or activity

  • Risky behavior

Manic Episodes

  • Symptoms last at least 1 week

  • Causes significant impairment, necessitates hospitalization, or includes psychotic features

Hypomanic episodes

  • Symptoms last at least 4 days

  • Clear change in functioning that is uncharacteristic, but not severe enough to cause significant impairment or hospitalization

Bipolar I disorder

At least one manic episode

  • Hypomanic or major depressive episode (s) may be present, but are not necessary for a diagnosis

  • Prevalence: ~-0.5%

  • Average age of onset: 18

Bipolar II disorder

At least one hypomanic episode and at least one major depressive episode

There has never been a manic episode

  • Prevalence: ~0.4%

  • Average age of onset: 20

  • 5 to 15% will eventually have a manic episode and receive a diagnosis of Bipolar I

Cyclothymic disorder

For 2 years or more, significant hypomanic and depressive symptoms that don’t meet either cut-off

They have never met criteria for a major depressive, manic, or hypomanic episode

Bipolar disorders: Etiology

Biological

Genetics:

  • Monozygotic twins- 40-70% likelihood

  • Dizygotic twins- 5-10% likelihood

  • General population- 1-2%

Social

Environmental stress:

  • (Hypo)manic episodes often precipitated by life stress, lack of sleep