July 18, 2016

Australia's First Modern Decline In Life Expectancy Due To Obesity

The headline above is as it appeared in the Puffington Host.  It is a crock.  You would think from it that Australian lifespans HAVE decreased.  They have not.  It is just another stupid Leftist theory that they might decrease -- even though they never have in recent decades.  There are many influences on lifespan, with obesity being only a minor one.

And a supreme piece of idiocy in the article below is that it takes no account of the TREND in obesity.  It takes no account of the fact that in many populations, obesity has stopped rising, and has even been declining in some populations over the last 10 years.  So even if we treat every word below as gospel, we don't know WHEN it refers to.  It may simply be a description of how things WERE.

Saying that lifespans will be reduced on the basis of a questionable assumption that obesity levels will increase is therefore an unsupported extrapolation and is very likely a wrong one for at least some groups -- a false prophecy.

I append the underlying journal article.  There is much of interest in it.  It is for a start a meta-analysis and it is amazing what people can get and do get out of a meta-analysis -- by selecting what you decide to include or exclude. Authors are very good at excluding from their analysis articles whose conclusions they dislike.

The original article appeared in the "Lancet", which was once a rightly respected journal.  Sad to say, the "Lancet" these days is Left-led. It even involved itself in propaganda about the Iraq war.  So biased meta-analyses in service of a "good cause" can be expected from it.  The obesity "war" is definitely a "good cause".

Secondly, there is much dispute now over whether BMI is a good index of obesity.  Very fit people can sometimes have a high BMI even though they have virtually no fat on them.

Thirdly, all the effects were very small, with Hazard Ratios below 2.0 except for the grossly obese.  The Federal Reference Manual on Scientific Evidence, Second Edition says (p. 384): "the threshold for concluding that an agent was more likely than not the cause of an individual's disease is a relative risk greater than 2.0."

So the only real concern is for the GROSSLY obese. That is in line with much previous research so the whole article below is just puffery. There are no substantial grounds to be concerned for the health of anybody over nearly all of the weight range


Australia has experienced an unprecedented collective weight gain over the last three decades and it could lead to the first modern decline in life expectancy.

A new mega-study on four million adults proved for the first time that an unhealthy Body Mass Index had a direct correlation with premature death.

The study published in British medical journal The Lancet found that for every increase in BMI unit after the overweight range, there was an increase in the risk of premature death by around one third.
This increased risk related to coronary heart disease, stroke, respiratory disease, diabetes complications and cancer.

Deakin University's World Health Organisation Collaborating Centre for Obesity Prevention professor Anna Peeters said the study pointed to a population-wide catastrophe in Australia.

"With two thirds of Australian adults overweight or obese this underscores the seriousness of current obesity rates for future life expectancy in Australia," Peeters said.

"If we needed yet another reason to step up our efforts to prevent obesity, this is it."

Cancer Council Australia chief executive Sanchia Aranda said cancer was one of the ways morbidity increased the risk of mortality.

"Given the unprecedented population weight gain in Australia over the last 30 years, we can expect to see the number of cancers and cancer deaths related to obesity and overweight increase in the future unless we take action," Aranda said.

SOURCE

Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents

Summary

Background

Overweight and obesity are increasing worldwide. To help assess their relevance to mortality in different populations we conducted individual-participant data meta-analyses of prospective studies of body-mass index (BMI), limiting confounding and reverse causality by restricting analyses to never-smokers and excluding pre-existing disease and the first 5 years of follow-up.

Methods

Of 10 625 411 participants in Asia, Australia and New Zealand, Europe, and North America from 239 prospective studies (median follow-up 13·7 years, IQR 11·4–14·7), 3 951 455 people in 189 studies were never-smokers without chronic diseases at recruitment who survived 5 years, of whom 385 879 died. The primary analyses are of these deaths, and study, age, and sex adjusted hazard ratios (HRs), relative to BMI 22·5–<25·0 kg/m2.

All-cause mortality was minimal at 20·0–25·0 kg/m2 (HR 1·00, 95% CI 0·98–1·02 for BMI 20·0–<22·5 kg/m2; 1·00, 0·99–1·01 for BMI 22·5–<25·0 kg/m2), and increased significantly both just below this range (1·13, 1·09–1·17 for BMI 18·5–<20·0 kg/m2; 1·51, 1·43–1·59 for BMI 15·0–<18·5) and throughout the overweight range (1·07, 1·07–1·08 for BMI 25·0–<27·5 kg/m2; 1·20, 1·18–1·22 for BMI 27·5–<30·0 kg/m2). The HR for obesity grade 1 (BMI 30·0–<35·0 kg/m2) was 1·45, 95% CI 1·41–1·48; the HR for obesity grade 2 (35·0–<40·0 kg/m2) was 1·94, 1·87–2·01; and the HR for obesity grade 3 (40·0–<60·0 kg/m2) was 2·76, 2·60–2·92. For BMI over 25·0 kg/m2, mortality increased approximately log-linearly with BMI; the HR per 5 kg/m2 units higher BMI was 1·39 (1·34–1·43) in Europe, 1·29 (1·26–1·32) in North America, 1·39 (1·34–1·44) in east Asia, and 1·31 (1·27–1·35) in Australia and New Zealand. This HR per 5 kg/m2 units higher BMI (for BMI over 25 kg/m2) was greater in younger than older people (1·52, 95% CI 1·47–1·56, for BMI measured at 35–49 years vs 1·21, 1·17–1·25, for BMI measured at 70–89 years; pheterogeneity<0·0001), greater in men than women (1·51, 1·46–1·56, vs 1·30, 1·26–1·33; pheterogeneity<0·0001), but similar in studies with self-reported and measured BMI.
Interpretation

The associations of both overweight and obesity with higher all-cause mortality were broadly consistent in four continents. This finding supports strategies to combat the entire spectrum of excess adiposity in many populations.

http://dx.doi.org/10.1016/S0140-6736(16)30175-1




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