Eating Disorders: Anorexia Nervosa Overview

Eating Disorders

• Anorexia Nervosa: Patients restrict energy intake to maintain extremely low body weight (typically BMI <18.5).
• Subtypes: Restricting (dieting/exercise) and binge-eating/purging (self-induced vomiting, laxatives).
• Symptoms: Emaciation, signs/symptoms secondary to starvation, parotid gland hypertrophy (in purging type), dental caries, halitosis, Russell's sign (calluses).
• Complications: Electrolyte imbalances (hypokalemia, hypochloremia, metabolic alkalosis), vital sign derangements, hypotension, hypothermia, bradycardia. Anemia, fractures, amenorrhea, lanugo, severe weight loss. Often comorbid with depression.
• Diagnosis: While amenorrhea was once included, it's not a required diagnostic criterion in DSM-5.
• Treatment: Psychotherapy and nutritional rehabilitation are first-line treatments. Hospitalization may be required for nutritional rehabilitation if vital signs are unstable, cardiac dysrhythmias, severe electrolyte imbalances, or severely low body weight.
• Refeeding Syndrome: A potentially life-threatening condition that arises when severely malnourished individuals abruptly regain weight. Carbohydrate ingestion initiates a surge of insulin, causing rapid uptake of potassium, phosphorus, and magnesium.

Sleeping Disorders

• Narcolepsy: A disorder of REM sleep characterized by excessive daytime sleepiness.
• Symptoms: Sleep attacks, cataplexy (loss of muscle tone), hypnagogic/hypnopompic hallucinations, sleep paralysis.
• Cause: Deficient hypocretin (orexin) production in the lateral hypothalamus.
• Complications: Electrolyte imbalances and cardiac arrhythmias from rapid nutritional restoration.
• Treatment: Focused on managing symptoms and improving sleep quality.

Insomnia

• Definition: A disorder characterized by difficulties initiating or maintaining sleep, or experiencing non-restorative sleep.
• Risk Factors: Anxiety, anticipatory anxiety, psychiatric disorders like depression.
• Symptoms: Difficulty initiating or maintaining sleep, frequent yawning, tiredness.
• Impact: Affects functioning in daily life.

Personality Disorders

• Personality Trait: A pervasive, repetitive pattern of perceiving, relating to, and thinking about the environment and oneself.
• Personality Disorder: An inflexible, maladaptive pattern of behavior causing subjective distress and/or impaired functioning, typically apparent in early adulthood.
• Cluster A (Weird): Odd or eccentric behaviors, with difficulty with relationships, schizoid (social isolation, limited emotional expression), paranoid (distrust and suspiciousness), schizotypal (magical thinking, eccentric appearance).
• Cluster B (Wild): Dramatic, emotional, or erratic behaviors. Borderline (unstable moods, relationships, self-harm), antisocial (disregard for others, criminality), histrionic (attention-seeking), narcissistic (grandiose, lack of empathy).
• Cluster C (Worried): Anxious or fearful behaviors. Avoidant (social inhibition, fear of rejection), obsessive-compulsive (preoccupation with order, perfectionism), dependent (submissiveness, need for care).