Tuesday, 18 August 2015

Why has diabetes increased? The answer may be economics rather than lifestyle


Over the last couple of days we've seen reports that the numbers of diagnoses for diabetes in the UK has risen by 60% over the last decade.

The number of people living with diabetes has soared by nearly 60% in the past decade, Diabetes UK warns.

The charity said more than 3.3 million people have some form of the condition, up from 2.1 million in 2005.

There's no disputing the accuracy of these figures or indeed the impact of the increase on the NHS (although claims it will 'bankrupt' the service are stretching the point a little). And we obviously need to know what it is that's causing the increase so as to try and prevent or mitigate those causes.

The most common 'cause' fingered in the reports is "lifestyle":

Martin McShane, national medical director for long term conditions at NHS England, said: “These figures are a stark warning and reveal the increasing cost of diabetes to the NHS. Evidence is piling up that added sugar and excess calories are causing avoidable increases in obesity and diabetes.

“We’ve said it before and we’ll say it again, it’s time to get serious about lifestyle change. Prevention is better than treatment for individual health as well as the health of the NHS.”

And let's be clear here about lifestyle. There's a well established link between morbid obesity and type-2 diabetes (which makes up 90% of the increase):

The relationship between obesity and diabetes is of such interdependence that the term 'diabesity' has been coined. The passage from obesity to diabetes is made by a progressive defect in insulin secretion coupled with a progressive rise in insulin resistance. Both insulin resistance and defective insulin secretion appear very prematurely in obese patients, and both worsen similarly towards diabetes.

So if there has been a significant increase in obesity, we would expect a comparable increase in type-2 diabetes. The problem is that this dramatic increase in diabetes has come during a period when the UK's rates of obesity were pretty stable (perhaps rising slightly):

If obesity is the main cause of new diabetes cases, this graph suggests that the increase should have been significantly less than 60%. So we have to look for another cause - perhaps it's something specific in the diet - sugar is the usual culprit here (mostly because diabetes is all about blood sugars and stuff like that so it stands to reason, doesn't it). Listening to a radio report on the story, I heard the interviewer ask something like "but it's not every kind of sugar is it, there are good sugars like the ones in fruit" - receiving a response all about 'five-a-day' rather than an accurate answer explaining how there's a link between fructose and type-2 diabetes (fructose being the dominant sugar in fruit).

It's worth therefore looking at whether sugar makes up more or less of our calories than it did a decade age - if there has been a substantial increase in sugar as an element in our diet and especially fructose then we might be able to point at that as a reason for the huge increase:

So here are some facts about the consumption of "non-milk extrinsic sugars" (this is all the added sugar as well as honey) in the UK. The figures come from the National Nutrition and Diet Survey (NNDS) conducted by the Government to provide a nationally representative snapshot of the nutritional intake and status of the UK population.

In 2000/01 NMES consumption in daily grammes was:

Male: 79
Female: 51

In 2008-20011 the average is:

Male: 70
Female: 50.1

So our sugar consumption has fallen. And this includes ALL forms of added sugar - the scary hidden stuff in processed food and the spoonful of lovely honey you stir into your hot toddy. Other than for women over 65 every category of consumption has fallen - with the biggest fall being among children.

We still eat a lot of sugar but there's no indication that it can be blamed directly for the increase in diabetes and especially type-2 diabetes. Despite all the shouting about diet and obesity, all the damnation of 'lifestyle', we're not really any closer to understanding why the last decade has seen such a big increase in diabetes. There is, however, one other thing that changed in 2004:

The new GP contract has been quoted as the most radical change to health care since the advent of the NHS in 1948. A major component of the contract is the Quality and Outcomes Framework (QOF). This offers a scoring system for achievement of health-care targets which is linked to financial rewards.

Put more simply - from 2004 family doctors were given a direct financial incentive to diagnose conditions that were within health-care targets and this included diabetes. Prior to 2004 few GPs ran routine diabetes tests - afterwards, with a direct financial incentive, loads more cases were identified. Don't get me wrong here, I'm not suggesting the incentive was a bad thing (it did mean lots more people got their diabetes treated who didn't before) but that it was perhaps the main reason why we saw a steady increase in diagnoses for diabetes.

Finally there's the matter of demographics - or to put it another way, how we're living longer:

You can see (perhaps) the impact of the rapid increase in obesity during the 1990s but look at the prevelance in the over-65s. Combine an incentive for GPs with an ageing population more likely to be visiting those GPs and we can see the source of our 60% rise. And this means that, rather than shouting about lifestyle, we should be celebrating just how well we've done in identifying diabetics - the task is to get that diabetes managed so as to avoid the expensive clinical interventions that are the big drivers of cost.

But then shouting about fat people and blaming sugar is much easier isn't it!



Anonymous said...

And of course the blood levels for a diagnosis of diabetes have been lowered so numbers increase dramatically as they have with hypertension, high cholesterol.

Anonymous said...

Didn't they also change the diagnostic perameters such that more people would test positive for the condition?


Patrick said...

Obesity doesn't immediately cause diabetes, so it could be the delayed result of an increase in obesity that occurred over the past fifteen to twenty years, but which is now levelling off. Or it could simply be the result of an aging population. Or it could be the result of incentives for GPs to diagnose the condition meaning it is being picked up earlier. Most likely, I'd guess it's a combination of all three.

Kin_Free said...

One other factor that no one seems to want to mention is the beneficial effects of smoking. You will note that diabetes has been increasing for several years as smoking prevalence has declined. (As has lung cancer, COPD and several other ailments previously claimed to be 'smoke related' but now often deemed to be 'non-communicable diseases', allegedly caused by all sorts of other individual lifestyle choices.)

"In the first three years after giving up, new quitters were 91 per cent more likely to develop diabetes. This decreased over time and after 12 years quitters had no excess risk."


It has been suggested that quitters invariably put on weight and that this could be the reason. As ever, these stark findings - that smoking can be good for you, are purported in each case to be an isolated, insignificant benefit. Smoking benefits are almost always played-down and tempered with the "Smoking cessation has many health benefits that outweigh this short-term effect" meme.

We see this rider added, by the anti-smoker industry, to all the many smoking benefits IF they are indeed admitted in the first place. Smokers are less likely to suffer from Alzheimer's, Parkinson's, Ulcerative colitis, gout etc. - 'but quitting smoking has more benefits'. You are more likely to survive a heart attack or stroke if you smoke - 'but quitting smoking has more benefits'. Smoking improves cognitive function in the healthy and not-so-healthy brain - 'but quitting is better'. The list of smoking benefits go on and on but in each case, according to tobacco CONTROL, the health and cognitive benefits are isolated and insignificant - 'quitting is better'. The anti-smoker industry is not interested in health - merely tobacco prohibition.

I am amazed that the medical profession often appears to passively comply with these nutters and their blinkered coercive dogma, instead of providing the full facts from which the public can weigh-up ALL the risks/rewards and decide for themselves what is good/not good for their health.

Guy Herbert said...

Nor does it pick on all groups equally, so it could be associated with a rise of and aging in the population of South Asian. Diabetes concern themselves say:

"Type 2 diabetes is up to six times more common in people of South Asian descent, and is a growing problem in the community. The South Asian community is also at risk of Type 2 diabetes from the age of 25, opposed to 40 in the White population."


Lifestyles are segmented, too. General sugar consumption and obesity may be falling, but there might be subcultures where both or either has risen over the same period. Some demographic and statistical untangling required.

Jonathan Bagley said...

Anonymous makes a good point. The definition has changed over the years and the critical level is now well into to fat part of the normal (bell curve) distribution. In this region a very small change defines a large extra number of people as diabetic.