Mood and Eating Disorders: Key Concepts and Diagnostic Criteria

Mood Disorders

Major Depressive Disorder (MDD)

Major Depressive Disorder is a common mood disorder characterized by persistent feelings of sadness and loss of interest. Diagnosis requires symptoms to last at least two weeks.

• Core Symptoms: Persistent depressed mood, loss of interest or pleasure (anhedonia).

• Other Symptoms:

  • Significant weight or appetite change

  • Insomnia or hypersomnia nearly every day

  • Psychomotor agitation or retardation nearly every day

  • Fatigue or loss of energy nearly every day

  • Feelings of worthlessness or excessive guilt nearly every day

  • Diminished ability to think or concentrate, indecisiveness nearly every day

• Diagnostic Criteria: Symptoms must cause significant distress or impairment and cannot be due to substances or a medical condition.

Persistent Depressive Disorder (Dysthymia)

Dysthymia is a chronic form of depression with a depressed mood lasting for at least two years (one year in children/adolescents).

• Symptoms:

  • Poor appetite or overeating

  • Insomnia or hypersomnia

  • Low energy or fatigue

  • Low self-esteem

  • Poor concentration

  • Feelings of hopelessness

Bipolar Disorder

Bipolar Disorder involves episodes of mania/hypomania and depression. Diagnosis requires at least one manic or hypomanic episode and one major depressive episode.

• Manic Episode:

  • Abnormally elevated, expansive, or irritable mood

  • Increased goal-directed activity or energy

  • Inflated self-esteem

  • Decreased need for sleep

  • Talkativeness

  • Flight of ideas

  • Distractibility

  • Risky behaviors

• Hypomanic Episode: Similar to mania but less severe and does not require hospitalization.

• Bipolar II Disorder: Characterized by hypomanic episodes and major depressive episodes, but no full manic episodes.

Substance Use Disorders

Substance Use Disorder

Substance Use Disorders are characterized by maladaptive patterns of substance use leading to significant impairment or distress.

• Symptoms:

  • Increase in quantity/frequency over time

  • Attempts to quit/cut back

  • Continued use despite problems

  • Pharmacological criteria (tolerance/withdrawal)

  • Impaired control (e.g., craving, taking more than intended)

  • Social impairment

  • Risky use

Trauma-Related Disorders

Post-Traumatic Stress Disorder (PTSD)

PTSD results from exposure to actual or threatened death, serious injury, or sexual violence.

• Core Symptoms:

  • Intrusion (e.g., flashbacks, nightmares)

  • Avoidance of trauma-related stimuli

  • Negative alterations in mood and cognition (e.g., guilt, detachment)

  • Alterations in arousal and reactivity (e.g., hypervigilance, irritability)

• Symptoms must persist for at least one month and cause distress or impairment.

Eating Disorders

Anorexia Nervosa

Anorexia Nervosa is characterized by restriction of energy intake, intense fear of gaining weight, and disturbance in body image.

• Symptoms:

  • Significantly low body weight

  • Intense fear of gaining weight or becoming fat

  • Persistent behavior that interferes with weight gain

• Subtypes:

  • Restricting type: No binge-eating or purging in the last 3 months

  • Binge-eating/purging type: Recurrent episodes of binge eating or purging (e.g., self-induced vomiting, misuse of laxatives, diuretics, or enemas)

Bulimia Nervosa

Bulimia Nervosa is characterized by recurrent episodes of binge eating followed by compensatory behaviors to prevent weight gain.

• Binge Eating: Eating, in a discrete period of time (within 2 hours), an amount of food that is larger than most people would eat in a similar period under similar circumstances.

• Compensatory Behaviors: Self-induced vomiting, misuse of laxatives, diuretics, fasting, or excessive exercise.

• Occurs at least once a week for 3 months.

• Self-Evaluation: Influenced by body shape and weight.

Binge Eating Disorder

Binge Eating Disorder is characterized by recurrent episodes of binge eating without inappropriate compensatory behaviors.

• Characteristics:

  • Eating, in a discrete period of time, an amount of food larger than most people would eat

  • Lack of control over eating during the episode

  • Episodes associated with at least three of the following:

    • Eating much more rapidly than normal

    • Eating until feeling uncomfortably full

    • Eating large amounts of food when not physically hungry

    • Eating alone due to embarrassment

    • Feeling disgusted, depressed, or guilty afterward

  • Marked distress regarding binge eating

  • Occurs at least once a week for 3 months

  • No recurrent use of inappropriate compensatory behaviors

Table: Comparison of Eating Disorders

Disorder	Core Features	Compensatory Behaviors	Frequency Criteria
Anorexia Nervosa	Restriction of intake, fear of weight gain, low body weight	May include purging (binge/purge subtype)	Persistent
Bulimia Nervosa	Binge eating, loss of control, concern with body shape/weight	Yes (vomiting, laxatives, etc.)	At least once/week for 3 months
Binge Eating Disorder	Binge eating, loss of control, marked distress	No	At least once/week for 3 months

Additional info: Diagnostic criteria and symptom lists have been expanded for clarity and completeness. Table inferred for comparison purposes.