5 Eating Disorders: Risk Factors & Pathophysiology PDF

**5 Eating Disorders** **Compare and Contrast the Risk Factors, Pathophysiological mechanisms and clinical manifestations of Anorexia Nervosa, Bulimia Nervosa, and Binge Eating Disorder** **1. Risk Factors** **Anorexia Nervosa (AN):** - Genetic predisposition, family history of eating disorder...

**5 Eating Disorders** **Compare and Contrast the Risk Factors, Pathophysiological mechanisms and clinical manifestations of Anorexia Nervosa, Bulimia Nervosa, and Binge Eating Disorder** **1. Risk Factors** **Anorexia Nervosa (AN):** - Genetic predisposition, family history of eating disorders or mood disorders. - Psychological factors: perfectionism, low self-esteem, body image dissatisfaction. - Environmental triggers: societal pressure for thinness, stressful life events. - Typically begins during adolescence or young adulthood. **Bulimia Nervosa (BN):** - Family history of eating disorders or substance abuse. - Psychological factors: impulsivity, emotional dysregulation. - Sociocultural influences: emphasis on physical appearance and dieting. - History of trauma or abuse. **Binge Eating Disorder (BED):** - Family history of obesity or eating disorders. - Psychological factors: emotional eating, low self-esteem, stress coping mechanisms. - Environmental factors: access to high-calorie foods, chronic dieting. - Comorbid psychiatric conditions such as depression or anxiety. **2. Pathophysiological Mechanisms** **Anorexia Nervosa:** - **Hypothalamic-pituitary axis dysfunction**: Low gonadotropin-releasing hormone leads to reduced estrogen/testosterone levels. - **Increased cortisol secretion**: Stress response activation contributes to catabolism. - **Neurotransmitter imbalances:** Low serotonin activity is linked to obsessive behaviors and mood disturbances. - **CNS neuropeptide dysregulation:** Altered regulation of neuropeptide-Y and leptin impacts appetite control. **Bulimia Nervosa:** - **Serotonin imbalance:** Implicated in impulsivity and binge-purge cycles. - **Dopamine dysregulation:** Altered reward processing promotes binge eating. - **Hypothalamic-pituitary-adrenal (HPA) axis activation:** Linked to stress and emotional eating. - **Electrolyte imbalances:** Vomiting and laxative use cause sodium and potassium depletion, leading to metabolic disturbances. **Binge Eating Disorder:** - **Dysregulated dopamine signaling:** Affects the brain's reward system, promoting overeating. - **Low inhibitory control of food intake:** Impaired signaling of satiety hormones (leptin, insulin). - **Hypothalamic dysfunction:** Abnormal activity in regions controlling hunger and fullness. - **Neuroinflammatory responses:** Chronic overeating leads to systemic inflammation, contributing to metabolic dysfunction. **3. Clinical Manifestations** **Anorexia Nervosa:** - Extreme weight loss (BMI \< 18.5). - Fear of gaining weight, distorted body image. - Amenorrhea (lack of menstruation) due to low body fat. - Fatigue, bradycardia (slow heart rate), low blood pressure. - Osteopenia or osteoporosis. **Bulimia Nervosa:** - Normal or slightly overweight body mass (unlike AN). - Recurrent episodes of binge eating followed by compensatory behavior (e.g., purging, laxatives, excessive exercise). - Pitted teeth and esophageal inflammation (due to vomiting). - Swollen salivary glands, electrolyte imbalances (hypokalemia), irregular heart rhythms. **Binge Eating Disorder:** - Recurrent episodes of consuming large amounts of food in a short time. - Lack of control over eating during episodes. - No compensatory behaviors (unlike BN). - Associated with obesity, type 2 diabetes, hypertension, and cardiovascular risks. - Emotional distress, guilt, and shame after eating episodes. **Summary Table:** **Aspect** **Anorexia Nervosa** **Bulimia Nervosa** **Binge Eating Disorder** ----------------------------- ------------------------------------------- ------------------------------------------------- --------------------------------------------------- **Risk Factors** Perfectionism, body image dissatisfaction Impulsivity, emotional dysregulation Emotional eating, chronic dieting **Pathophysiology** HPA axis dysfunction, low serotonin Serotonin imbalance, dopamine dysregulation Dysregulated dopamine signaling, leptin imbalance **Clinical Manifestations** Underweight, amenorrhea, bradycardia Normal weight, pitted teeth, electrolyte issues Obesity, metabolic disorders, emotional distress