AIM • FINAL YEAR MBBS • MS MODULE • KMU CURRICULUM
Student Memory Support
Topic 1. Obesity, Weight Dysregulation & Eating Disorders
Rapid high-yield reinforcement after AIM Learning Material
1. High-Yield Flashcards
Tap a question to reveal its answer.
How is adult obesity classified by BMI?
BMI ≥30 kg/m²; class I 30–34.9, II 35–39.9, III ≥40.
Why assess waist circumference in obesity?
It estimates central adiposity and adds cardiometabolic risk information beyond BMI.
Why can metabolic risk occur at lower BMI in South Asian adults?
Visceral adiposity and metabolic complications may develop at lower BMI.
Which physiological changes encourage weight regain?
Increased appetite and decreased energy expenditure after weight loss.
What obesity mechanism contributes to insulin resistance?
Visceral adiposity increases free fatty acids and inflammatory signaling.
Why does obesity aggravate knee osteoarthritis?
Extra mechanical loading stresses weight-bearing joints.
Which clinical signs suggest metabolic consequences of obesity?
Raised BP, abnormal glucose, dyslipidemia or acanthosis nigricans.
How does orlistat reduce weight?
It inhibits intestinal lipases, reducing dietary fat absorption.
What key adverse effects are associated with orlistat?
Oily stools, urgency and reduced absorption of fat-soluble vitamins.
What is the main weight-loss effect of GLP-1 receptor agonists?
Enhanced satiety and reduced food intake; nausea and vomiting are common.
What are two key bariatric operations?
Sleeve gastrectomy and Roux-en-Y gastric bypass.
What long-term care is needed after bariatric surgery?
Lifelong nutritional surveillance and appropriate micronutrient supplements.
What distinguishes anorexia nervosa clinically?
Restriction with significantly low weight and intense fear of weight gain or weight-gain-preventing behaviors.
What distinguishes bulimia nervosa clinically?
Recurrent binge eating with loss of control and compensatory behaviors; BMI may be normal.
What is a vomiting-related biochemical disturbance in bulimia?
Hypokalemic, hypochloremic metabolic alkalosis.
What makes anorexia nervosa an urgent medical problem?
Marked bradycardia, hypotension, syncope, arrhythmia or severe malnutrition.
What is the major nutritional rehabilitation hazard in severe malnutrition?
Refeeding syndrome, especially hypophosphatemia.
Which psychological treatment is central for bulimia nervosa?
Eating-disorder-focused cognitive behavioral therapy; fluoxetine can be an adjunct.
2. Mnemonics
Obesity complication domains
MEC-P
M — Musculoskeletal (osteoarthritis); E — Endocrine/metabolic (insulin resistance); C — Cardiovascular (hypertension/CAD); P — Psychological (depression/anxiety).
Obesity medication checkpoints
A-S-M
A — Adverse effects; S — Safety/contraindications; M — Monitoring of weight, BP, glycemic risk and nutrition.
Bulimia clinical pattern
B-P-E
B — Binge with loss of control; P — Purging/compensation; E — Electrolyte depletion, especially from vomiting.
3. Memory Tables
Anorexia Nervosa vs Bulimia Nervosa
| Feature | Anorexia nervosa | Bulimia nervosa |
|---|---|---|
| Core pattern | Restriction with significantly low weight | Binge eating plus compensatory behavior |
| Weight | Significantly low | May be normal |
| Characteristic complication | Bradycardia, low bone density | Dental erosion, electrolyte depletion |
| Care focus | Medical stability + nutritional restoration | Psychological treatment + medical assessment |
4. Rapid Revision Points — Last-Minute Revision
- BMI is a screening measure; assess waist and obesity-related illness rather than relying on BMI alone.
- Use age- and sex-specific BMI growth references in children.
- Weight regain can reflect adaptive hunger and reduced energy expenditure.
- Visceral fat promotes insulin resistance and cardiometabolic risk.
- Sustainable nutrition, physical activity and behavioral support underpin treatment.
- Orlistat can cause oily stools and fat-soluble vitamin malabsorption.
- GLP-1-based drugs support satiety but commonly cause gastrointestinal symptoms.
- Bariatric surgery requires preoperative assessment and lifelong nutritional follow-up.
- Restrictive low-weight anorexia and binge-compensate bulimia have different diagnostic patterns.
- Medical instability in eating disorders takes priority over routine outpatient therapy.
5. Clinical Memory Hooks
Central obesity + hypertension + high glucose → Assess cardiometabolic complications, not just weight.
Persistent vomiting after bariatric surgery + ataxia → Suspect thiamine deficiency; urgent treatment.
Low-weight restriction + bradycardia → Anorexia nervosa with possible medical instability.
Binge–purge episodes + dental enamel erosion → Bulimia nervosa; assess potassium and acid–base disturbance.
6. Starred High-Yield Exam Points
- ⭐ Adult BMI ≥30 kg/m² defines obesity under standard WHO criteria; risk may occur below this in South Asians.
- ⭐ Orlistat blocks gastrointestinal lipases; avoid it in chronic malabsorption.
- ⭐ Family or personal medullary thyroid carcinoma/MEN2 history is a major contraindication for relevant GLP-1-based agents.
- ⭐ After bariatric surgery, monitor iron, B12, calcium, vitamin D and thiamine.
- ⭐ Anorexia with syncope, hypotension or arrhythmia needs urgent medical assessment.
- ⭐ Vomiting in bulimia can cause hypokalemic metabolic alkalosis.
- ⭐ Refeeding after severe malnutrition can cause dangerous hypophosphatemia.