After an extended (Canadian) Thanksgiving Weekend, it is back to regular blogging about the manifold aspects of obesity prevention and management.

As an internist, it continues to be difficult to accept that the most effective treatment for severe obesity today is surgery (even if there remains an important role for internists to play in manageing these patients).

Nevertheless, for anyone, who remains skeptical despite the rapidly accumulating data on the safety, success and cost-effectiveness of obesity surgery, I would like to refer you to the latest systematic review on this subject, just published in Health Technology Assessment.

The report was commissioned by the UK Health Technology Assessment (HTA) programme, part of the National Institute for Health Research (NIHR), which directly influences decision-making bodies such as the National Institute for Health and Clinical Excellence (NICE) and the National Screening Committee (NSC).

For this report Joanna Picot and colleagues from the University of Southampton, UK, identified a total of 5386 references of which 26 were included in the clinical effectiveness review: three randomised controlled trials (RCTs) and three cohort studies compared surgery with non-surgical interventions and 20 RCTs compared different surgical procedures.

Bariatric surgery was consistently more effective for weight loss than non-surgical options. In one large cohort study weight loss was still apparent 10 years after surgery, whereas patients receiving conventional treatment had gained weight. Some measures of QoL improved after surgery, but not others. After surgery statistically fewer people had metabolic syndrome and there was higher remission of Type 2 diabetes than in non-surgical groups. In one large cohort study the incidence of three out of six comorbidities assessed 10 years after surgery was significantly reduced compared with conventional therapy.

Gastric bypass (GBP) was more effective for weight loss than vertical banded gastroplasty (VBG) and adjustable gastric banding (AGB). Laparoscopic isolated sleeve gastrectomy (LISG) was more effective than AGB in one study.

Comorbidities after surgery improved in all groups, but with no significant differences between different surgical interventions.

Mortality ranged from none to 10%. Major adverse events following surgery, some necessitating reoperation, included anastomosis leakage, pneumonia, pulmonary embolism, band slippage and band erosion.

Based on an economic model developed by the authors, surgical management was more costly than non-surgical management, but resulted in improved outcomes.

For morbid obesity, incremental cost-effectiveness ratios (ICERs) (base case) ranged between 2000 pounds and 4000 pounds per Quality-Adjusted Life Year (QALY) gained and remained within the range regarded as cost-effective from an NHS decision-making perspective even when assumptions for deterministic sensitivity analysis were changed.

The report concludes that bariatric surgery appears to be a clinically effective and cost-effective intervention for moderately to severely obese people compared with non-surgical interventions.

Nevertheless, uncertainties remain regarding several important aspects including impact on patient quality of life, impact of surgeon experience on outcome, late complications leading to reoperation, duration of comorbidity remission, and resource utilisation.

Patients struggling with severe obesity can only hope that the responsible decision makers will take this report into account as they hopefully rapidly ramp up access to this much-needed management option.

Free Download: NIHR Health Technology Assessment of Bariatric Surgery 2009 Executive Summary

Free Download: NIHR Health Technology Assessment of Bariatric Surgery 2009 Full Report

AMS
Edmonton, Alberta

The link between lower socioeconomic status and obesity has been well documented (at least for Western women). While this is often attributed to the increased expense of healthy foods, it may well be that increased psychosocial stressors including food insecurity, low-walkability neighbourhoods, higher density of fast-food outlets, anxiety, depression and other mental health problems also contribute.

A new study by Eva Münster and colleagues from the University of Mainz, Germany, just published in BMC Public Health suggests that over-indebtedness may be a further factor in promoting weight gain. Over-indebtedness can be defined as lack of possible debt redemption in due time due to the relation of income and cost of living even after a remarkable cutback in standard of living.

Münster and colleagues examined data from a cross-sectional study on over-indebtedness and health including 949 over-indebted subjects from 2006 and 2007 and an independent representative telephone health survey of 8318 subjects.

After adjusting for socio-economic (age, sex, education, income) and health factors (depression, smoking), the over-indebted individuals were almost twice as llikely to be overweight and almost 2.5-times as likely to be obese than non-over-indebted individuals.

It is estimated that, as a result of the recent financial turmoil, about 3 million German households (7.6 %) corresponding to more than 6 million residents are currently over-indebted.

In their discussion, the authors focus heavily on the possible contribution of the expense of healthy foods, although they do acknoweldge the fact that at times of financial distress, individuals may be more preoccupied with issues other than living healthy lifestyles.

I would further suggest that the very same psychosocial behaviours that promote over-indebtness (risk-taking, impulsiveness, poor-planning, etc.) may also promote weight gain, especially in our current obesogenic environment.

At least the study suggests that there is little reason to assume that financial distress will result in people eating less - if at all, the opposite appears true.

AMS
Edmonton, Alberta

While I am taking a brief break from clinics and other obligations (including daily blog posts), I will be reposting past articles, which I still believe to be relevant but may have escaped the attention of the 100s of new readers who have signed up in the past months.

The following was first posted on 24/11/07

The link between two major problems of our times, global warming and the obesity epidemic, may be closer than we think.

The following are a few random thoughts on why I believe solving one will go a long way to solving the other.

If we accept that a major contribution to the rising incidence of obesity is (energy) overconsumption and lack of physical activity, then reducing consumption and increasing physical activity will be important.

But reducing consumption and increasing physical activity will also help reduce global warming - here is why:

Over the past century, fossil fuels have increasingly displaced food as the energy source for human movement. Both occupational and domestic physical activity has been replaced by automation and labor-saving devices, all of which consume energy from fossil fuels. But not just automation, also the physical effort to move from one place to another is today largely dependent on fossil fuels.

As people get larger the fuels consumed to move the extra weight around only adds to the problem. It was estimated that in 2000, US airlines spent $275 million to burn 350 million more gallons of fuel just to carry the additional weight of Americans. Obviously, it also takes more fuel to move heavier people around on the ground whether this is in cars or on elevators, escalators or amusement park rides.

But increased use of fossil fuels is not just part of the activity equation. The use of fossil fuels is also intimately linked to our food. World-wide, agricultural activity, especially livestock production (including ruminant methane production, transport and feed), accounts for about one fifth of total greenhouse-gas emissions.

In most industrialised countries today the total energy put into food production vastly exceeds the food energy yield [see McMichael et al. for in depth discussion of this topic].

As energy inputs, mainly in the form of fossil fuels, have gradually increased, the energy ratio (energy out/energy in) in agriculture has decreased from being close to 100 for traditional pre-industrial societies to less than 1 in the present food system. Each calorie of food you eat may have consumed 10 to 50 calories in fossil fuels (the exact number depends on how you calculate this relationship - but no matter how you do it, the numbers are scary).

Processing 1 pound of coffee requires more than 8,000 calories of fossil fuel, the equivalent of one quart of crude oil, 30 cubic feet of natural gas or 2 1/2 lbs of coal. It has been estimated that the CO2 emissions attributable to producing, processing, packaging and distributing the food consumed by a family of four is about 8 tonnes a year. (For more on this click here).

Not surprisingly, many environmental organisations are now targeting built environments, transportation as well as food production and supply as major culprits in global warming. How do some of these issues relate to obesity prevention?

Rebuilding our cities to allow shorter trip distances will also allow changes in travel mode (e.g. walking or bicycling instead of driving). When it comes to both the environment and to obesity, urban sprawl is a killer!

Compact densely populated neighbourhoods where the majority of trips can be done by active transport paired with efficient urban public-transport systems powered by renewable energy would not only reduce local air pollution and greenhouse emissions but would also reduce traffic injuries and improve the safety of neighbourhoods (more people on the street!).

Creation of human-scale, mixed-use urban “villages” with unique identities, improved local services, neighbourhood events and activities, accessible public transport including high-quality pavements, cycle paths, lighting and public art will get people out and moving - thereby reducing both greenhouse gases and increasing physical activity. (for an in-depth analysis of these issues refer to Woodcock et al. in the Lancet series on Energy and Health).

Perhaps the key to both global warming and the obesity epidemic may be in living, working and eating local.

Is this utopia? To some perhaps, but the alternative is scary!

AMS

As an internist, who does not perform operations on people, it is indeed humbling having to acknowledge that surgery is perhaps the best treatment for severe obesity, something widely considered a “medical” condition. To add insult to injury, there is now an accumulating body of evidence that illustrates not only that bariatric surgery is one of the most effective treatments known to man in terms of reducing morbidity and mortality, but also a treatment that can literally save the health care system billions of dollars.

This slightly embarrassing (for non-surgeons) fact is once again illustrated by the latest study on this topic just published in this month’s issue of Diabetes Care by Catherine Keating and colleagues from Monash University, Melbourne, Australia.

In this paper, the researchers compared the cost-effectiveness of surgically induced weight loss to conventional therapy for the management of recently diagnosed type 2 diabetes in class I/II obese patients. The analysis compares the lifetime costs and quality-adjusted life-years (QALYs) between two intervention groups: surgically treated patients vs. conventionally treated obese patients with type 2 diabetes.

Intervention costs were extrapolated based on observed resource utilization during the trial. Health care costs for patients with type 2 diabetes and outcome variables required to derive estimates of QALYs (Quality-Adjusted Life Years) were sourced from published literature. A health care system perspective was adopted for the analysis. Costs and outcomes were discounted annually at 3% and presented in 2006 Australian dollars (AUD) (current currency exchange: 1 AUD = 0.87 CND).

The mean number of years in diabetes remission over a lifetime was 11.4 for surgical therapy patients and 2.1 for conventional therapy patients. Over the remainder of their lifetime, surgical and conventional therapy patients lived 15.7 and 14.5 discounted QALYs, respectively.

The mean discounted lifetime costs were 98,900 AUD per surgical therapy patient and 101,400 AUD per conventional therapy patient. Relative to conventional therapy, surgically induced weight loss was associated with a mean health care saving of 2,400 AUD and 1.2 additional QALYs per patient.

Obviously, when extrapolated to the millions of patients diagnosed with type 2 diabetes, most of who have Class 1 obesity (or greater), the potential savings are in the billions.

And this analysis only accounts for the saving from treating diabetes - when you add the costs for reducing heart disease, cancers, need for joint replacements, incontinence, sleep apnea, liver disease, fertility treatments and other important obesity related comorbidities, the savings to the health care system are probably in the 10s of billions. Remember, this analysis looked at class I and II obesity - the potential savings are far greater in patients with more severe obesity.

So what is stopping us from offering more obesity surgery to the 100s of 1000s of Canadians who would benefit. Is it simply bias and discrimination against obese people? Or do we really think that somehow magically the obesity epidemic will suddenly disappear?

As I’ve written before, no health system can afford to NOT increase spending on obesity management. If we don’t, we will never have enough diabetes centres, heart hospitals, cancer wards or orthopedic clinics to deal with the multitudes of patients disabled and defeated by obesity.

As the authors of this study conclude, surgically induced weight loss is a dominant intervention (it both saves health care costs and generates health benefits) for managing recently diagnosed type 2 diabetes in class I/II obese patients in Australia - I have no doubt that the savings would be as great in Canada.

AMS
Edmonton, Alberta

Last week Statistics Canada released a new report on obesity and how it affects the Canadian Workforce.

The findings were based on an analysis of the nationally representative Canadian Community Health and National Population Health Surveys.

The following key findings are taken from the report:

- In 2005, 15.7% of employed Canadians aged 18 to 64, or more than two million people, were obese, up from 12.5% in the mid-1990s.

- Obesity was most prevalent among older workers aged 55 to 64, 21% of whom were obese in 2005. This held for both men and women, although the prevalence was lower among women.

- The odds of being absent from work were almost four times higher for obese young men aged 18 to 34 than for those with normal weight, after controlling for socioeconomic and health-related factors.

- Obesity was also related to reduced work activities, more disability days, and higher rates of work injury for women aged 35 to 54.

- Low education significantly increased the odds of obesity for both men and women. Women with low personal income were more likely to be obese than high-income earners.

- Compared with men in white-collar jobs, a higher proportion of blue-collar workers were obese.

- Men working longer hours (more than 40 per week) were also more likely to be obese than regular full-time workers who worked 30 to 40 hours per week.

- Compared with regular-schedule workers, a greater proportion of shift workers, both men and women, were obese.

- Obesity was also related to elevated levels of work stress. Obese workers reported higher job strain and lower support from co-workers.

Overall the report confirms numerous issues that are consistent with the literature: association between obesity and low education, poor income, high stress levels, shift work.

I was quoted by Shannon Proudfoot of CanWest in articles picked up across the Canadian media as follows:

“Obesity really is a societal problem,” said Dr. Arya M. Sharma, scientific director of the Canadian Obesity Network. “We’ve virtually eliminated physical activity from the workplace . . . We have to make up the lost physical activity in our spare time.”

“In Sharma’s opinion, the trend towards obesity in the workplace is unlikely to improve. The economic downturn, he said, will create stress for both employed and unemployed people, leading to an increase in stress-related eating. People are also less likely to eat healthy food, he said, and will cut back expenditures, such as sports and gym fees”

I have little to add - as blogged before - the true cost of obesity is NOT in health care!

AMS
Edmonton, Alberta