Overweight and Obesity

 

 

Prevalence of Overweight and Obesity

Obesity is increasing around the world, and in many locations is replacing or adding to the devestation of malnutrition and infectious diseases.

 

Childhood obesity is defined as in the 95th percentile, while overweight is between 85-95 percentile.

 

In most of Canada, over 20% of the adult population is obese, while the prevalence of overweight is 59%. Arya Sharma, Alberta doc, says, based on Australian estimates, annual cost of obesity in Canada is $95 billion.

 

The rate in aboriginal Canadians is 1.6x higher than the national average.

Worryingly, the proportion of children aged 6-11 who are overweight has doubled over the past 25 years, while the percentage of overweight adolescents has tripled.

 

Depending on region, between 17.6-27.9% of Nova Scotians are obese.

According to Katzamarzyk and Ardern, over 9% of adult deaths in Canada can be attributed to overweight and obesity.

 

 

 

Measures of Obesity

 

Body Mass Index (BMI)

The BMI is useful for predicting future health risk.

underweight is less than 18.5

normal is 18.5 - 25

overweight is 25 - 30

obese is 30+

severe obesity

morbid obesity

 

It is calculated as weight over height squared, given in kg/m2.

Make sure person is wearing no shoes, is standing tall (give their neck a tug upwards) and heels are against the wall. No tiptoes! Use a horizonal bar to measure.

BMI is the most common measure, and is correlated with body fat, but does not provide important information on fat distribution. People can jump to silly conclusions if they perform a BMI on athletes, pregnant women, or folks with ascites.

 

 

Children

In children, overweight and obesity are calculated on growth charts; overweight between 85-95th percentile; obesity is over 95th percentile

 

Waist Circumference (WC)

WC is increasingly recognized as a critical measure of health. It is highly correlated to BMI and total adiposity, but is also, importantly, correlated with intra-abdominal obesity and insulin resistance.

 

Men should be below 40 inches (102 cm), while women should be below 35 in (88 cm)

 

Measure WC at the top of the iliac crest, with the tape snug and parallel to the floor. Measure when the person has breathed out.

 

People of different ethnicities have different cutoff points. At a given WC, black women have less risk than white women, while Asian men have more risk than white men.

 

 

 

Causes and Risk Factors for Obesity

 

eating a lot

not exercising enough

genes

SES

 

Health Risks of Obesity

Life expectancy drops with obesity. The link between obesity and coronary artery disease is not straightforward, though it appears diabetes and hypertension are critical linkages.

 

cardiovascular

insulin resistance and type II diabetes

 

pulmonary disease

cancer

Other increased infammatory markers effects

overweight children

70% become overweight or obsese as adults

80% if one or more parents is overweight

increased cardiovascular risk

social consequence: fewer married, lower jobs

 

 

The Costs of Obesity

 

Obesity can lead to increased short term disability claims, health care costs, and days off work.


“Obesity cost the Nation as much as $102 billion for direct costs alone in 1999”
• $6.7 - $7.4 billion for arthritis;
• $25.5 - $30.6 billion for heart disease;
• $18.4 - $20.5 billion for type 2 diabetes;
• $8.3 - $9.6 billion for hypertension; and
• $6.1 - $8.1 billion for stroke.

American Obesity Association/The Lewin Group. Costs of Obesity. September 13, 2000.

 

 

 

 

Obesity Discrimination

there is a term 'fatism' describing negative views of obese people by society, employers, and customers. It is more significant in women than men and can be powerful and devestating.

 

 

Managing Patients with Obesity

Need a good understanding of mental, mechanical, metabolic, and monetary challenges patients face.

 

Measure and assess weight

Clincial exam: blood pressure, heart rate

Lab investgations: fasting glucose, lipid profile

Assess and screen for depression, eating disorders

Assess readiness to change

Come up with program to lose 5-10% of body weight, or 0.5-1 kg (1-2lb) per week for 6 months

Bring in the health care team

CBT

reduce calories by 500-1000 cal/daily

start exercise, with medical evaluation beforehand

 

 

bariatric surgery

Surgery is an option for adults when

for children:

restrictuve: assist in portion control and early satiety

adjustable gastric band (AGB)

gastric sleeve resection

malabsorptive: biliary-pancreatic switch

 

Roux-en-Y gastric bypass (RYGB)

 

mixed:etc

 

 

References and Resources

Ogden et al, 2008. JAMA (pediatric obesity)

Katzmarzyk & Ardern. Can J Public Health 2004;95:16-20.

Story MT, Neumark-Stzainer DR, et al. 2002. Pediatrics

 

Fontaine et al. 2003. JAMA - years of life lost due to obseity

 

Harris CMAJ 2009 - school-based activities don't work for weight loss