Today, I am speaking at the XII Congreso Internacional Avances en Medicina 2010 hosted by the Hospital Civil de Guadalajara (Thank you Juan Ricardo Lopez y Taylor for the kind invitation!).

There is indeed no denying that Mexico, as does everyone else in North America, has a substantial obesity problem.

As recently pointed out by Dudley Althaus, who writes for the Houston Chronicle:

“Though still afflicted by large pockets of the malnourished poor, Mexico is fat and quickly getting fatter, its children gaining weight faster than anyone else in the country.

About 70 percent of Mexican adults are now overweight, according to government estimates, more than triple the number of three decades ago. Also, about a third of the country’s schoolchildren and teenagers are overweight, making Mexicans the second-heaviest people on the planet, gaining quickly on their American neighbors.

With more people living in urban areas, and some with more money, Mexicans are eating more and exercising less. Forgoing the beans, tortillas, fruit and vegetables their grandparents ate, people flock to U.S.-style fast food.

Also, calorie-laden Mexican dishes once reserved for special occasions have become routine fare. Anything fried, packaged pastries, soft drinks and candy are widely available.”

Not surprisingly, last month, Mexican President Felipe Calderon launched a national campaign against obesity (beating the US Obama initiative by a few weeks) and called on parents, teachers and the food industry to guide people to more healthful living.

Whether or not this appeal will indeed have any noticeable impact on the obesity epidemic remains to be seen.  From my conversations with fellow delegates, at least the interest and concerns amongst health professionals seems considerable - but so does their sense of helplessness.

To read more by Dudley Althaus on the obesity problem in Mexico click here.

AMS
Guadalajara, Mexico

Despite the wide-spread concern about the health impact of the childhood obesity epidemic, there is actually not much data that directly shows how this excess weight may affect mortality.

Such data is now available at least for native American kids, from a study by Paul Franks (National Institutes of Health, Phoenix, AZ) and colleagues, just published in the New England Journal of Medicine.

The researchers analysed data from a cohort of 4857 American Indian (Pima or Tohono O’odham Indian) children without diabetes (mean age, 11.3 years) born between 1945 and 1984.

During a median follow-up period of around 24 years, death rates from endogenous causes among children in the highest quartile of BMI were more than double those among children in the lowest BMI quartile.

Similarly, rates of death from endogenous causes among children in the highest quartile of glucose intolerance were 73% higher than those among children in the lowest quartile and childhood hypertension was significantly associated with a 60% increased risk of premature death from endogenous causes.

Thus, at least in native Americans, childhood obesity is a significant risk factor for premature death - certainly a warning for those who believe that early obesity is something you can simply grow out of.

Given the raging epidemic of childhood obesity amongst the First Nations, Inuit, and Métis populations in Canada, these data should certainly prompt decisive action to address obesity amongst its native peoples.

AMS
Edmonton, Alberta

Yesterday, the Heart and Stroke Foundation of Canada released a report titled “A Perfect Storm” in which they present an alarming increase in hypertension and other cardiovascular risk factors in young adults.

According to this report, currently over 160,000 Canadians aged 20-30 and over 340,000 Canadians aged 35-44 are hypertensive.

This should really not come as a surprise, as the same report states that currently 40.5% or 2,5 million 20-30 year olds and 51.5% or another 2.4 million 35-44 year olds are overweight or obese.

Why, given these obesity numbers, does this increase in hypertension not surprise me in the least?

Because, as someone who has extensively worked on the relationship between excess weight and blood pressure, I am only all too familiar with the profound effect that overweight and obesity can have on blood pressure - especially in the young!

Thus, as we reported in a paper that was published back in 2004 in the American Journal of Hypertension, overweight and obesity are indeed the primary drivers of hypertension in the young.

In this cross-sectional study of 45,125 unselected consecutive primary care attendees in a representative nationwide sample of 1912 primary care physicians in Germany, we not only found that blood pressure levels were consistently higher in obese patients (increasing from 34.3% in normal weight to 60.6% in overweight, and well over 70% in obese individuals), but that this increase was also associated with markedly poorer blood pressure control rates (odds-ratio for good blood pressure control in diagnosed and treated patients was 0.8 in overweight and as low as 0.5 in obese patients).

However, even more relevant to yesterday’s report, was the clear finding that the younger the patients, the greater the impact of excess weight on their blood pressure.

As seen in the figure (click figure to enlarge), while in patients older than 60 years, there was little impact of BMI class on hypertension prevalence, in younger patients, there was a steep and consistent increase in hypertension rates with increasing BMI.

This is not surprising, when we look at the pathophysiology of hypertension, which in older individuals is driven almost entirely by stiffening of arteries and an increase in peripheral resistance (or in other words “aging”), while in younger individuals hypertension is driven mainly by the increased sympathetic activity, volume expansion, and increased cardiac output typically associated with excess weight.

Let us not forget that the prevalence of diabetes in the young (over 66,000 in 20-30 year olds and over 130,000 in 35-44 year olds according to the report) is also virtually entirely driven by overweight and obesity.

If all of this is not enough to get us to focus all our efforts on preventing and treating overweight and obesity, I don’t know what is.

If we want to prevent hypertension and diabetes in the young, we need to prevent overweight and obesity.

If we want to treat hypertension and diabetes in the young, we need to treat overweight and obesity.

It is that simple!

AMS
Edmonton, Alberta.

Yesterday, Statistics Canada released its latest report on obesity in Canada.

The report focussed on the latest data from the Canadian Health Measures Survey, which included around 1,000 participants who wore accelerometers for seven consecutive days to objectively measure their levels of physical activity. Additional measurements included tests for physical fitness, flexibility, and anthropometric measures of body size and fat distribution.

Compared to earlier data (albeit collected with less precise methods), there is no doubt that over the past 20 years, Canadians have gotten bigger and less fit. Even more concerning perhaps is the marked increase in abdominal obesity.

None of this bodes well for the health of Canadians. Among the many media interviews I gave yesterday, a quote that perhaps stands out was the one cited by The Canadian Press: “If you look at those numbers I’d be very surprised to see what actually qualifies as a national crisis if this does not.”

The problem is that this is a crisis that is evolving in slow motion and therefore it is easy to not address this problem with the urgency devoted to other more spectacular health problems.

As Yoni Freedhoff pointed out in his blog Weighty Matters a few days ago:

“So 25,000 obesity and diet related deaths a year and what type of interventions are we seeing? None… Can you imagine how much money and resources would be spent and how much public awareness would be stirred up if West Nile virus killed 25,000 people each and every year?“

Where is the National Obesity Task Force forming to address this issue? Where is the Obesity Commission being constituted to work on solutions? Where are the public outcries for Obesity Action Plans? 

Perhaps it is all too easy to blame the individual rather than accepting the fact that obesity is the direct result of the circumstances we have collectively created for ourselves as a society - no one, not one of us, can wash our hands in innocence. 

As I blogged recently, according to the recent WHO/OECD report, even in a best-case scenario, we are unlikely to see population-wide prevention efforts leading to a significant reversal in obesity rates in the next few decades.

This should not serve as an excuse to do nothing - let’s at least start by ensuring that the increasing number of kids and adults already struggling with excess weight have access to evidence-based obesity treatments today.

AMS
Edmonton, Alberta

Over the past 15 years, smoking rates in the US have declined by 20%, whereas obesity rates have increased by 48%.

A new analysis published in the New England Journal of Medicine by Susan Stewart and colleagues from Harvard University, Boston, MA, forecasts the effect of trends in obesity and smoking on future U.S. life expectancy and quality-adjusted life expectancy.

The researchers used data from the past three decades to forecast future rates of obesity and smoking and estimate their effects on length and quality of life.

The net effect of the declines in smoking and the increases in BMI for an 18-year old is a reduction in life expectancy of 0.71 years and a reduction in quality-adjusted life expectancy of 0.91 years relative to the trend. This pattern of results is seen for every year between 2005 and 2020 and becomes more pronounced over time.

The calculations assume that if past trends continue, almost half the U.S. adult population will meet the WHO criteria for obesity by 2020 (currently the obesity rate already exceeds 35% in some states).

Obviously, these forecasts are at a population level and do not apply to a particular person who loses weight or stops smoking.

While these results do not imply that life expectancy will fall, they do suggest that as a result of increasing obesity rates life expectancy will rise less rapidly than it otherwise would.

While these are US data, there is little reason to assume that similar trends will not also be apparent in other countries including Canada.

Clearly, policy makers will likely now need to address obesity with the same vehemence as they did smoking - unfortunately, finding and implementing effective policies to reduce obesity makes smoking bans look like a walk in the park (no pun intended).

AMS
Edmonton, Alberta