Obesity Flashcards
What is obesity?
■ Obesity means the deposition of excess fat in
the body and is caused by ingestion of greater
amounts of food than can be utilised by the
body as energy.
■ In addition, there is an imbalance between the
amount of food consumed and exercise taken on
a daily basis.
■ “a disorder of excess body fatness that is associated with an increased risk of disease” (World Health Organisation Technical Consultation, 2000)
Where is fat stored?
■ Foods that are high in fat are used for energy -
if excessive amounts of these foods are
consumed, fat is stored in adipose tissue and
carbohydrate is stored as glycogen in the liver
and muscle
What are the 2 x ways obesity impacts the body? (v brief)
■ The effects of obesity on the body
include both obvious physical changes,
due to the increased mass of fatty
tissue,
and
■ changes at the cellular and metabolic
level due to increased production of
various products by enlarged fat cells.
What is anthropometry?
■ Anthropometry is used to assess and
predict performance, health and survival
of individuals and reflect the economic
and social well being of populations.
■ Anthropometry is a widely used,
inexpensive and non-invasive measure of
the general nutritional status of an
individual or a population group.
e.g. height/weight weight for age weight for height height for age Mid-upper arm circumference BMI
Define Obesity
“a disorder of excess body fatness that
is associated with an increased risk of
disease”
(World Health Organisation Technical Consultation, 2000)
The World Health Organization (WHO)
criteria for defining overweight and obesity
is based on the body mass index (BMI) score.
What is BMI? and what are ranges?
This is calculated as weight in kilograms
divided by height in metres squared.
Classification of underweight, normal weight, overweight and obesity & Risk of comorbidities Underweight <18.5 Low Normal range 18.5-24.9 Average Overweight >25 Pre-obese 25.0-29.9 Mildly increased Obese >30 Class I 30.0-34.9 Moderate Class II 35.0- 39.9 Severe Class III >40.0 Very Severe
Prevalence of obesity in the UK?
NHS Digital 2017
PREVELANCE OF OBESITY IN ENGLAND (NHS
Digital, 2017)
■ In 2015, 58% of women and 68% of men were
overweight or obese.
■ Obesity prevalence increased from 15% in 1993
to 27% in 2015.
■ In 2015/16, over 1 in 5 children in Reception,
and over 1 in 3 children in Year 6 were
measured as obese or overweight.
■ In 2015/16 there were 525 thousand admissions
in NHS hospitals where obesity was recorded as
a factor.
■ Over three quarters of bariatric surgery
patients were aged between 35 and 54, and
over three quarters of patients were female.
Prevalence of obesity worldwide?
Estimate: >300 million adults worldwide are obese, > than 1 billion are overweight and a further 115 million
people suffer related problems ranging
from premature death to a reduced overall quality of life.
■ Enormous public health issue, with serious physical, psychological and social
effects on the population.
Which generic medications cause obesity?
Beta blockers Insulin Oral contraceptive Anti-convulsants Gabapentin
Which psychiatric medications cause obesity?
Antidepressants - mirtazapine
Antipsychotic drugs: most
Mood stabiliser: lithium, carbamazepine, sodium valproate
Pregabalin
3 x metabolic factors predictive of weight gain?
- Low sedentary energy expenditure
- High respiratory quotient (carb to fat oxidation ratio)
- Low levels of spontaneous physical activity
Maternal obesity associated with what risks?
Increased risk of:
Birth defects
First trimester and recurrent miscarriage
Difficulties in assessing the foetus
Errors in BP measurements
Difficulties in care-giving
Pre-eclampsia
Gestational diabetes
Difficulties with intubation - esp in morbidly obese range (leading cause of mat death in relation to anasthesia)
What risks are associated with obesity?
All-causes of death at any given age (mortality)
Coronary heart disease, stroke, hypertension,
hyperlipidemia, and Type 2 Diabetes.
High LDL cholesterol or low HDL cholesterol
Sleep apnoea
Breast, endometrial, ovarian, liver and colon
cancer
Gallbladder disease
Musculoskeletal disorders/ Osteoarthritis (a breakdown of
cartilage and bone within a joint)
Infertility and sexual dysfunction; urinary incontinence;
Non Alcoholic Liver Disease
Obesity is also indirectly related to anxiety, low self esteem, impaired social interaction, and clinical depression
Body pain and difficulty with physical functioning
Obesity puts children, adolescents, and adults at a
higher risk of secondary health problems like type 2
diabetes, asthma, cardiovascular disease, orthopaedic
problems, sleep apnoea, breast, colon, and endometrial
cancers, stroke, osteoarthritis, and gynaecological
&& mental health problems?
What risks are associated with childhood / adolescent obesity?
Increased risk of premature mortality
Reduced quality of life
Chronic inflammation
Presence and clustering of cardiovascular and
metabolic risk factors
Fatty liver
Asthma exacerbations
■ Long-term (for the adult who was obese as a
child or adolescent)
Persistence of obesity
Poor long-term educational and economic
attainment
Increased risk of poor psychosocial health
Links between MH and obesity?
S&EMI
• People with diagnoses of severe and enduring
mental illness such as schizophrenia and bipolar
disorders are at increased risk for a range of
physical illnesses and conditions including
coronary heart disease, diabetes, infections,
respiratory disease and greater levels of obesity.
• They are almost 2x as likely to die from
coronary heart disease as the general population
and 4x more likely to die from respiratory disease
• In many cases, obesity and weight gain are a
clear side effect of medication
Overweight and obesity among adults Health Survey for England 2012 to 2014 (three-year average)
Overweight M/F?
Obese M/F?
7/10 Men overweight
6/10 Women overweight
1/4 men and women are obese (25%)
Obesity Trend?
Increasing, though seemingly beginning to plateaux
Effects of obesity on:
Circulatory System
Raised BMI increases the risk of hypertension
(high blood pressure), which is itself a risk
factor for coronary heart disease and stroke
and can contribute to other conditions such as
renal failure.
■ The risk of coronary heart disease (including
heart attacks and heart failure) and stroke are
both substantially increased.
■ Risks of deep vein thrombosis and pulmonary
embolism are also increased.
High blood pressure - what happens?
■ High Blood Pressure- Additional fat tissue in the
body needs oxygen and nutrients in order to live,
which requires the blood vessels to circulate
more blood to the fat tissue.
■ This increases the workload of the heart because it must pump more blood through additional
blood vessels. More circulating blood also means more pressure on the artery walls.
■ Higher pressure on the artery walls increases the
blood pressure. In addition, extra weight can raise the heart rate and reduce the body’s ability to transport blood through the vessels.
- CHD due to fatty desposits increasing shearing stress, damaging inner linings
- artherosclerosis
- schistocytes
- can cause MI or angina
- Blood clots can cause stroke
Heart disease in obesity vs. non obese?
Heart disease – Atherosclerosis (hardening of the
arteries) is present 10 times more often in obese
people compared to those who are not obese.
Diabetes link?
■ Diabetes- Obesity is the major cause of Type 2
Diabetes
■ This type of diabetes usually begins in adulthood
but, is now actually occurring in children.
■ Obesity can cause resistance to insulin, the
hormone that regulates blood sugar. When
obesity causes insulin resistance, the blood
sugar becomes elevated.
■ Even moderate obesity dramatically increases
the risk of diabetes.
■ A person with type 2 diabetes has insulin
resistance, meaning their pancreas doesn’t
produce enough insulin or the body doesn’t
react properly to insulin.
■ Studies suggest that abdominal fat causes fat
cells to release ‘pro-inflammatory’ chemicals,
which can make the body less sensitive to the
insulin it produces by disrupting the function of
insulin responsive cells and their ability to
respond to insulin.
■ This is known as insulin resistance - the hallmark of type 2 diabetes.
■ Glucose transport into most tissues is achieved by the action of molecules called glucose transporters e.g. GLUT-4 receptor
■ These molecules transport glucose by diffusion down concentration gradients
■ Insulin resistance in adipose cells is
associated with a decrease in GLUT4 transporter number and activity
More prone to infection
Causing Acanthosis nigricans (insulin resistance)
Joint problems?
■ Joint problems, including osteoarthrosis
■ This is a non-inflammatory joint disease
characterized by degeneration of the joint
cartilage
■ Obesity can affect the knees and hips because of
the stress placed on the joints by extra weight.
■ Joint replacement surgery, while commonly
performed on damaged joints, may not be an
advisable option for an obese person because the
artificial joint has a higher risk of loosening and
causing further damage.
