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, or a BMI >30, while overweight is between 85-95 percentile. 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.
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.
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.
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.
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+
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.
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 (88-90 cm), depending on guidelines and ethnicity.
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.
In children, overweight and obesity are calculated on growth charts; overweight between 85-95th percentile; obesity is over 95th percentile.
a simple case introducing clincial presentation and calling for a differential diagnosis to get students thinking.
Obesity is caused by an energy intake greater than expenditure.
It is important to consider, and screen for, other conditions, such as:
Secondary causes are rare, but include:
Primary causes include:
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.
In Canada, almost 25% of women of childbearing age are obese.
Assess readiness to change
Assess and screen for depression, eating disorders
The motivational interviewing approach will be used here, though there are many other paradigms that can be adopted and adapted.
Risk factors that may pose a challenge include:
Health Canada recommends children have 90 minutes of moderate or vigorous activity daily.
For kids who are getting less activity, or who are overweight,
sometimes parents need permission to impose limits
BMI 85-95% - at risk of overweight
BMI above 95% - overweight (obese in the US)
Raise BMI concerns gently with parents
Clincial exam: blood pressure, heart rate
fasting glucose, lipid profile
Need a good understanding of mental, mechanical, metabolic, and monetary challenges patients face.
It is vital that the patient be fully involved in goal-setting.
Numerically, it is reasonable to aim for decreases of 5-10%, or 0.5-1kg/week, for six months.
Bring in the health care team
Ongoing self-awareness is important. This includes regular weigh-ins, documentation of successes and failures.
Addressing anxiety and depression should occur.
It is helpful to work with a dietitian in setting nutritional goals. Some helpful strategies include:
Regular exercise is important, to increase basal metabolism and calorie expendature.
After physical exam to ensure no cardiac risk factors are present, begin with 30 minutes of moderate activity, 3-5 days/week, and increase this to 60 minutes daily, most days.
Anti-obesity drugs are designed to:
Surgery is an option for adults when:
restrictive: assist in portion control and early satiety
adjustable gastric band (AGB)
gastric sleeve resection
malabsorptive: biliary-pancreatic switch
Roux-en-Y gastric bypass (RYGB)
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.
The Edmonton Obesity Staging System appears to be one of the most effective means of predicting mortality (Padwal et al, 2011).
Ogden et al, 2008. JAMA (pediatric obesity)
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