Obesity

Question 1

What is obesity?

Answer 1

• BMI > 30 kg/m2 
• Can be defined using waist circumference:
  Men:
• Low Risk = < 94 cm 
• Very High Risk = > 102 cm 
  Women:
  *Low Risk = < 80 cm 
  *Very High Risk = > 88 cm 

Question 2

What are the different classes of obesity?

Answer 2

overweight: 25-29.9 Kg/m2
Class I obesity: 30-34.9 Kg/m2
Class II obesity: 35-39.9 Kg/m2
Class III: more than or 40 Kg/m2

Question 3

Aetiology/Risk factors of obesity

Answer 3

• There are genetic factors that affect the risk of become obese 
• There are a few monogenic forms of obesity (e.g. leptin deficiency, Prader-Willi syndrome) 
• Common obesity is caused by energy intake > energy usage 

Question 4

What are the presenting symptoms of obesity?

Answer 4

• joint pain
• fatigue
• snoring
• dyspnea
• depression

Question 5

What co-morbidities are associated with obesity?

Answer 5

• metabolic syndrome
• Diabetes M
• Hypertension
• Dyslipidemia

Question 6

What signs of obesity can be found on physical examination?

Answer 6

• excess adipose tissue
• increased waist circumference
• abdominal striae
• acanthosis nigricans
• lower extremity edema

Question 7

What investigations are used to diagnose/ monitor obesity?

Answer 7

• Measure serum lipids 
• Measure HbA1c 
• Hormone profile (check for hormonal cause of obesity) 
• TFTs - hypothyroidism can cause obesity 
• Other investigations depending on comorbidities 

Question 8

How can obesity be managed?

Answer 8

1. Dietary changes 
   - For weight reduction, an intake of 1000-1200 kcal/day for women and 1200-1500 kcal/day for men should produce a caloric deficit of 500-1000 kcal/day. 
   - Traditionally, the most important aspect of diet and exercise was to ensure that the caloric intake was less than the caloric expenditure, thus producing a caloric deficit. 
   - At 6-month follow-up, the low-carbohydrate/high-protein diet has been found to produce greater weight loss than the low-fat diet, and patients seemed to prefer the low-carbohydrate/high-protein diet. 
2. Increase in physical activity 
3. Adjunctive psychological therapy 
   - Adding psychological therapy is an effective adjunct to diet and exercise, and is recommended in all receptive patients. 
4. Adjunctive pharmacotherapy 
   - Pharmacotherapy is indicated as an adjunct to diet and exercise in people whose BMI is ≥30 kg/m², or >27 kg/m² if associated with obesity-related comorbidity. 
5. Bariatric surgery 
   - In general, bariatric surgery reduces caloric intake by altering hunger and fullness through changes to the stomach, small intestine, or a hybrid of both. 

Question 9

Describe the prognosis of obesity

Answer 9

Diet and exercise alone typically produces a modest decrease (5% to 10%) in body weight over the short term, but the relapse rate can reach beyond 50%, depending on the length of the follow-up period. 

Question 10

Describe the pathophysiology behind obesity

Answer 10

In the typical person, the mechanism by which an imbalance between energy intake and expenditure occurs is concerned primarily with the regulation of appetite, metabolism, and physical activity. This constellation of processes may also be referred to as energy homeostasis (i.e., the regulation of substrate intake, processing, and utilisation). 

Question 11

Describe the epidemiology of obesity

Answer 11

24% of men and 25% of women are obese