Obesity Flashcards
What is obesity?
A complex disease involving an excessive amount of body fat
What four complications are associated with obesity?
Heart disease
Diabetes
High blood pressure
Certain cancers
How do we calculate an individual’s BMI?
We divide the patient’s weight (kg) by their height (m2)
What is an underweight BMI?
BMI below 18
What is a normal BMI?
BMI between 18.5 to 24.9
What is an overweight BMI?
BMI between 25 to 29.9
What is an obesity class I BMI?
BMI between 30 to 34.9
What is an obesity class II BMI?
BMI between 35 to 39.9
What is an obesity class III BMI?
BMI greater or equal to 40
What do we aim to achieve when managing obesity patients?
To stabilise the patient at a healthy weight
This improves their overall health and lowers their risk of developing complications related to obesity
What weight loss % do we aim for in obesity patients?
The initial treatment goal is to achieve a weight loss 5% to 10% of the patient’s total body weight
However, the more weight a patients loses, the greater the benefits
How do we conservatively treat obesity?
Dietary modifications
Regular exercise
What dietary modifications do we advise in obesity patients?
To reduce calorie intake and make healthier eating choices
It is important that they make gradual, realistic changes so that they can maintain any weight loss permanently.
We encourage patients to participate in a comprehensive weight loss program for at least six months and in the maintenance phase of a program for at least a year to boost their odds of weight loss success
How much exercise should obesity patients take part in a week?
At least 150 minutes a week of moderate-intensity physical activity
How much exercise should obesity patients take part in a week to achieve significant weight loss?
300 minutes or more a week
What is the function of anti-obesity medications?
To help patients stick to a low-calorie diet by decreasing their appetite.
When would we consider pharmacological treatment of obesity?
If patients have a BMI over 30
If patients have a BMI greater than 28 with associated medical complications
What is the main anti-obesity medication?
Orlistat
What is the function of orlistat?
It inhibits fat absorption through inhibition of pancreatic and gastric lipases
What dose of orlistat can be bought over the counter? What two criteria must patients meet to purchase it?
60mg
BMI greater than 28 and be over the age of eighteen
What is the prescription dose of orlistat?
120mg three times daily, before each meal
What happens when patients consume a high quantity of fat whilst taking orlistat?
Fatty diarrhoea
How long do we prescribe orlistat for?
A trial period of twelve weeks
It is only continued if the patient has lost at least 5% of their initial body weight since starting the treatment
What is the function of bariatric surgeries?
They either limit the amount of food the patient can comfortably eat or decreases their absorption of food
How much weight can individual loose from bariatric surgery?
35% or more of their excess body weight
When do we consider bariatric surgery in obesity patients?
BMI greater than 40
BMI over 35 with associated medical complications
Which patients do we prioritise bariatric surgery in?
Patients aged between 18-44 with a BMI between 35-40kg/m2 and recent (less than five years) onset of type two diabetes
What are the three types of bariatric surgery?
Gastric band surgery
Gastric bypass surgery
Sleeve gastrectomy surgery
What is gastric band surgery? How does it encourage weight loss?
In gastric band surgery, an inflatable band separates the stomach into two pouches
This means that only a small distension of the stomach will result in nerve fibres sending signals to the brain that the stomach is full
The patient will therefore feel less hungry and stop eating after a small consumption of food
What are the complications of gastric band surgery?
The gastric band becoming too tight or too loose
If the band is too tight, patients will have a liquid-based diet, which will therefore result in weight gain
What two bariatric surgeries are more common?
Gastric bypass surgery
Sleeve gastrectomy surgery
What is gastric bypass surgery? How does it encourage weight loss?
In gastric bypass surgery, the surgeon anastomoses the small intestine to the fundus opening of the stomach
This means that food can only enter a small pouch of the stomach before entering the small bowel
How much weight loss can patients loose with gastric bypass surgery?
30% of total weight loss
What is a complication of gastric bypass surgery?
Dumping syndrome
What is the pathophysiology of Dumping syndrome?
It occurs as a result of hyperosomolar load rapidly entering the proximal jejunum
The process of osmosis drags water into the lumen, resulting in luminal distension then diarrhoea
What are the three clinical features of Dumping syndrome?
Crampy abdominal pain
Diarrhoea
Vertigo
What is sleeve gastrectomy surgery? How does it encourage weight loss?
In sleeve gastrectomy surgery, the surgeon removes the majority of the fundus of the stomach
Grehlin is a hormone produced by the fundus, which causes a feeling of hunger
Therefore, by removing the fundus less of this hormone is produced and patients therefore don’t feel hungry as often
What syndrome results in children having a reduced tone, hypogonadism and obesity?
Prader-Willi syndrome
Where is the leptin hormone released?
Adipose tissue
What is the function of leptin? What is the mechanism behind this action?
It decreases appetite
It increases secretion of melanocyte-stimulating hormone (MSH) and corticotrophin-releasing hormone (CRH) from the hypothalamus
In which two locations is the gherlin hormone released?
P/D1 cells lining the fundus of the stomach
Epsilon cells of the pancreas
What are the two functions of gherlin?
It increases appetite
It increases growth hormone secretion
What two cancers are associated with obesity?
Breast cancer
Endometrial cancer
What is metabolic syndrome?
It is a clustering of cardiovascular disease risk factors
The underlying pathophysiology is related to insulin resistance and visceral/central obesity
What is the diagnostic criteria for metabolic syndrome?
The criteria consists of three or more….
Increased waist circumference (dependent on ethnicity) or a BMI >30
Dyslipidaemia with raised triglycerides >150 mg/dL or reduced HDL-cholesterol
Hypertension
Impaired glucose tolerance
