Obesity Flashcards
Provide diseases and health problems associated with enlarged fat cells and visceral fat in obesity?
1) coronary heart disease
2) diabetes
3) stroke
4) cancer
5) hypertension
6) dyslipidemia (low HDL and high triglyceride levels)
7) endocrine changes (insulin resistance)
Diseases related to BMI will cost the NHS how much each year in 2025?
£25.1 billion
Provide problems associated with an increased body mass in obesity?
1) bone and joint diseases (osteoarthritis, back disorders)
2) pulmonary diseases (sleep apnea, pulmonary embolism, and sleep-disordered breathing)
3) social stigmatisation
Outline the Framingham study by Moore et al., 2005?
A modest weight loss of 6.8kg led to a 28% reduction in the risk for hypertension among middle age adults and a 37% reduction amongst older adults.
How is obesity diagnosed?
BMI is used to define:
Overweight: 25>29.9 kg/m2
Obesity: >30kg/m2
What is the best predictor of weight related health?
Waist circumference and Waist to hip ratio correlated better with CVD risk rather than BMI.
What 3 things should clinicians consider as causes of obesity?
1) endocrine disorders
2) neuroendocrine disorders
3) genetic disorders
Provide two types of fat patterning?
1) Android obesity (Apple Shape) male
2) Gynoid obesity (Pear Shape) female
Are males or females at a greater risk due to fat patterning and why?
Males are at a greater risk because of fat patterning around the abdominal region and visceral fat near to the organs.
Name all 5 abdominal adipose tissue depots?
1) Omental adipose tissue
2) Mesenteric adipose tissue
3) Retroperitoneal adipose tissue
4) Deep subcutaneous adipose tissue
5) Superficial subcutaneous adipose tissue
Increasing fat deposits in which three abdominal adipose tissue depots increases the risk of disease?
1) Omental adipose tissue
2) Mesenteric adipose tissue
3) Retroperitoneal adipose tissue
Energy balance determines an individuals weight loss or weight gain, what 4 factors influence energy balance?
1) Eating
2) Activity
3) Thermic effect of Food
4) Basal energy
The Thermic effect of eating (-10%), the Thermic effect of physical activity (15-30%), and resting metabolic rate (60-75%) all influence total daily energy expenditure (TEE). True or false?
True
What 4 factors can influence resting metabolic rate?
1) fat free body mass
2) gender
3) thyroid hormones
4) protein turnover
There are two types of fat deposits; upper and lower body. Define the location of these fat deposits?
Lower body: all adipose tissue below the inguinal ligament anteriorly and the iliac crest posteriorly.
Upper body: all adipose tissue in the abdominal and breast region.
Under normal circumstances upper body adipose acts as a reservoir for meal free fatty acid storage and release. True or false?
True
What are adipocytes?
Adipocytes are fat cells that store energy as fat.
Define lipolysis?
Lipolysis is the breakdown of lipids and involves hydrolysis of triglycerides into FFA, FFA undergo beta-oxidation to produce Acetyl units, subsequently producing ATP in the kerbs cycle.
Adipocytes in obesity appear to become resistant to the anti lipolytic effects of insulin. True or false?
True
What is hyperinsulineamia?
Lots of insulin circulating in the blood
Very low-density lipoproteins are associated with atherosclerosis and increased plaque deposits, the or false?
True
Increased FFA influences endothelial cells ability to control blood pressure by nitric-oxide mediated dilation, true or false?
True
High circulating FFA are associated with hypertension and endothelial dysfunction. True or false?
True
Increased hypertension is associated with an increased risk of hypertension. True or false?
True
Leptin resistance causes what 2 things?
1) high levels of circulating leptin
2) increased renal sympathetic activity
Increased FFA into the portal vein activates the sympathetic nervous system. True or false?
True
Adipocytes release:
Potent minerlocorticoid (class of steroid hormones) releasing factors that increase levels of aldosterone
Name two vasoconstrictors that cause endothelial dysfunction by down regulating nitric-oxide, and increase the risk of atherosclerosis?
1) endothelin-1
2) vascular cell adhesion molecule (VCAM)
A decreased nitric-oxide responsiveness is a common abnormality amongst obese individuals that leads to endothelial dysfunction. True or false?
True
………. and ………. abnormalities can explain high arterial blood pressure in obesity.
Central
Peripheral
High levels of circulating FFA activate what two systems?
1) sympathetic nervous activity
2) renin-angiotensin system (RAS)
What is the renin-angiotensin system (RAS)?
The Renin-angiotensin system (RAS) is a hormone that regulates blood pressure and water fluid balance.
Obesity is associated with endothelial dysfunction and renal function abnormalities that play a key role in ……………….?
Hypertension
Briefly outline the leptin resistance pathway.
Leptin is released from the adipocytes, and high levels of circulating leptin causes over stimulation of the leptin receptors within the hypothalamus and increases renal sympathetic activity.
- In the liver, Renin is then involved in the conversion of Angiotensinogen to angiotensin 1.
- Angiotensin 1 is then converted to angiotensin 2 by the angiotensin converting enzyme (ACE).
- Angiotensin 2 is a potent vaso-active peptide that causes vasoconstriction of the blood vessels which drives up blood pressure.
- Angiotensin 2 also stimulates the secretion of the hormone aldosterone from the adrenal cortex, which promotes sodium and water retention increasing the the volume of fluid in the body and therefore and increased blood pressure.
The increased production of what vasoconstrictor amongst patients with a high body mass is a potential mechanism associated with endothelial dysfunction?
Endothelin-1
As there is much evidence to support that there is an increased activation of the renin-angiotensin system (RAS) in obese individuals, this has led to the notion that the blockade of RAS might be a beneficial strategy for the management of hypertension. True or False?
True
Name two things that can cause insulin resistance?
1) High levels of visceral adiposity
2) high levels of circulating FFA
Insulin resistance can lead to:
1) Glucose Intolerance
2) Diabetes
Insulin resistance is coupled with ……………… And increases the risk of hypotension and the development of CVD and cancers.
Hyperinsulinemia (high levels of circulating insulin).