Consequences of obesity Flashcards
What are the main ways of assessing obesity?
BMI WHR WHH (waist: height) waist circumference hydrodensitometry dual energy x-ray absorptiometry
What are the benefits of using BMI to assess obesity?
correlates significantly with body fat, morbidity and mortality
What are the main categories of weight classification by BMI?
Underweight < 18.5
Normal 18.5 – 24.9
Overweight 25.0– 29.9
Obesity_1 30.0- 34.9
Severely obese 35.0-29.9
Morbidly obese >40
What is defined as being SUPER OBESE?
BMI >50
What are the complications associated with being super obese?
- osteoarthritis
- cardiopulmonary failure
- metabolic syndrome (DM, NASH, HTN, hyperlipidaemia)
Are there specific Rx to combat the complications of superobesity?
No
Metabolic syndrome improves with 5-10% weight loss
What are the main causes of obesity?
- nutrient and energy imbalance
- genetics
- behavioural and culture factors
What are the main contributors to weight gain?
- socio-economic status
- smoking cessation
- hormonal
- inactivity
- psychosocial/emotions
- medications
What can the increasing prevalence of obesity over past 20-30 years be attributed to?
Reduced resting metabolic rate Reduced muscle mass Increased fat mass Increased accumulation of abdominal adipose tissue
What 3 process are dysregulated in obesity?
energy intake
adipose tissue formation
energy expenditure
What are the main complications of obesity?
Hypertension Stroke Diabetes mellitus, Type 2 Metabolic syndrome CV mortality Cancer – endometrium, breast, prostate, and colon. Gallbladder disease Osteoarthritis Respiratory diseases and sleep-apnea
What are the 2 main types of body patterns observed in obesity?
APPLE SHAPED
- intra-abdominal or visceral
- visceral fat deposition
PEAR SHAPED
- lower body or external type
- subcutaneous fat deposition
both are linked to elevated levels of FFAs
What is the nature of adipocytes found in the visceral depots?
- large insulin-resistant adipocytes
- increased adrenergic receptors
- catecholamine mediated lipolysis
inverse correlation between visceral fat % and insulin sensitivity
What is the nature of adipocytes found in the subcutaneous depots?
- small insulin-sensitive adipocytes
- reduced adrenergic receptors
What is the insulin resistance syndrome?
= physiologic response is inadequate for the amount of insulin secreted
What are other names for metabolic syndrome?
- syndrome X
- dysmetabolic syndrome
- insulin resistance syndrome
What are the main components of insulin resistance?
- complex dyslipidaemia
- endothelial dysfunction
- systemic inflammation
- atherosclerosis
- disordered fibrinolysis
- hypertension
- T2DM
- visceral obesity
When is dysmetabolic syndrome thought to occur?
When insulin resistance results in atherosclerosis
What are clinical manifestations of insulin resistance syndrome?
Central obesity Glucose intolerance Atherosclerosis Hypertension Polycystic ovary syndrome
What are the biochemical abnormalities of insulin resistance?
Insulin resistance
Hyperinsulinemia
High TG
Low HDL-C
Small, dense LDL
Increased PAI-1
How does hyperglycaemia and hyperinsulinaemia result in hypertension?
Activation of the sympathetic nervous system
Increase of arterial tone
Na+ reabsorption
How does hyperglycaemia and hyperinsulinaemia result in T2DM?
Overstimulation of pancreatic -cell function
Reduction of insulin secretion
What is the correlation between high BMI and BP?
70% in men
60% women
association between excess adiposity and hypertension
What 3 metabolic mechanisms promote hypertension in obesity?
INCREASED
- vasconstriction
- cardiac output
- sodium reabsorption
