Mood Disorders Overview

Mood Disorders Overview

  • Mood disorders involve significant mood changes over extended periods.
  • Two main categories of mood disorders:
    • Depressive Disorders: Characterized by only depressive episodes.
    • Bipolar Disorder (Manic Depression): Characterized by alternating manic and depressive episodes.

Periods of Mood Disorders

  • Mania: Intense feelings of euphoria and excitement.
  • Depression: Profound sadness and dejection.
  • Both states can alternate in distinct periods.

Unipolar Mood Disorders: Major Depressive Disorder (MDD)

  • Symptoms for Diagnosis: Presence of symptoms for over two weeks without prior manic episodes.
  • Duration: Untreated MDD lasts approximately 6-9 months.
  • Subtypes of MDD:
    • Single Episode: One depressive episode.
    • Recurrent Episodes: Two or more episodes with at least two months in between.
  • Persistent Depressive Disorder: Chronic depression lasting for at least two years (one year for children).

Recurrence of Depression

  • Recurrence Types:
    • Relapse: Symptoms return shortly after previous symptoms ended.
    • Recurrence: Full depressive symptoms return after a period of absence.
  • Statistics: 40-50% of MDD patients experience recurrence.
  • Factors contributing to prolonging depression include high genetic risk and life stressors.

Common Symptoms of Major Depressive Disorder

  • Loss of interest (anhedonia).
  • Altered sleep patterns (insomnia/hypersomnia).
  • Changes in appetite (increase/decrease).
  • Psychomotor symptoms:
    • Retardation: Slowed behaviors leading to accidents.
    • Agitation: Involuntary fidgeting and restlessness.

DSM-5 Criteria for MDD

  • At least five of the following must be present:
    • Depressed mood or loss of interest most days.
    • Recurring thoughts of death/suicide.
    • Significant changes in sleep or appetite.
    • Fatigue or loss of energy.
    • Impaired concentration or indecisiveness.
    • Feelings of worthlessness or excessive guilt.
    • Symptoms not due to physiological effects or medical conditions.

Subtypes of MDD Explained

  • Anxiety Features: Anxiety symptoms co-occurring with depressive symptoms.
  • Mixed Features: Meeting criteria for depression with some manic symptoms.
  • Atypical Features: Mood improves in response to positive events.
  • Melancholic Features: Lack of interest/enjoyment in activities.
  • Catatonic Features: Includes psychomotor disturbances.
  • Psychotic Features: Experiencing hallucinations/delusions aligned with depression.
  • Seasonal Pattern (SAD): Depression linked to seasonal changes.
  • Peripartum Onset: Depression related to pregnancy or post-birth.

Comorbidity in Depressive Disorders

  • Over 75% of individuals with depression have at least one other disorder (e.g., anxiety, substance use).
  • Differential patterns for men (substance abuse) and women (anxiety disorders).

Prevalence of MDD

  • Estimated 16% of adults in the U.S. experience MDD.
  • Commonly develops in ages 18-29; difficult to detect in older adults.
  • Prevalence statistics for children and adolescents: 1–3% schoolchildren and 15%–20% adolescents.
  • Gender disparities: women are twice as likely to be diagnosed as men.

Causal Factors of Depressive Disorders

Biological Factors
  • Hormones: Affect appetite, sleep, and pleasure perception; HPA axis hyperactivity.
  • Neurochemical changes: Imbalances in norepinephrine, serotonin, and dopamine.
  • Sleep cycles: Disturbances lead to hypersomnia or insomnia during episodes.
Psychological Factors
  • Correlation between marital problems and clinical depression.
  • High vulnerability among neurotic individuals; introversion can exacerbate risks.
  • Stressful life events are significant predictors of depression.
Behavioral Theories
  • Stressful life events can reduce positive reinforcement, leading to depression.
  • Learned Helplessness Theory: Perception of lack of control contributes to depression.
Cognitive Theories
  • Beck's Cognitive Theory: Negative cognitive patterns precede depression.
  • Abramson's Revised Helplessness Theory: Emphasis on hopelessness and attributional style.
Interpersonal Theories
  • Focus on relationship difficulties and need for support; rejection sensitivity.
Sociocultural Factors
  • Cultural differences affect susceptibility and expression of depressive disorders.
Gender Difference Theories
  • Different theories account for higher prevalence among women (stressors, roles, and societal expectations).

Bipolar and Related Disorders Overview

  • Bipolar I Disorder: Characterized by severe episodes of depression and mania.
  • Bipolar II Disorder: Involves milder manic episodes.
  • Cyclothymic Disorder: Chronic, less severe mood changes for at least two years.

Symptoms of Manic Episodes

  • Elevated mood, increased energy, and self-esteem; possible irritability or aggression.
  • DSM-5 Criteria for Mania:
    • Lasting elevated mood for at least one week and accompanied by 3+ symptoms (e.g., grandiosity, distractibility).

Causal Factors of Bipolar Disorders

  • Strong genetic links; environmental triggers can exacerbate episodes.
  • Structural brain abnormalities related to emotional processing are implicated.

Treatment Options for Mood Disorders

Biological Treatments
  • Antidepressants: Varying effectiveness; SSRIs and SNRIs are common first-line treatments.
  • Mood Stabilizers: Help manage bipolar disorder symptoms.
  • Electroconvulsive Therapy: For severe cases, particularly when other treatments fail.
Psychological Treatments
  • Cognitive Behavioral Therapy (CBT): Focus on modifying cognitive distortions and behaviors.
  • Interpersonal Therapy (IPT): Address interpersonal issues and improve social functioning.
Other Treatments
  • Light Therapy: Effective for seasonal affective disorder (SAD).
  • Vagus Nerve Stimulation (VNS): An emerging treatment option.
  • Deep Brain Stimulation: Last resort for treatment-resistant cases.