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BRITISH BROADCASTING CORPORATION
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CASE NOTES
Programme 4. - Metabolic Syndrome
RADIO 4
TUESDAY 22nd January 2008 2100-2130
PRESENTER: MARK PORTER
REPORTER: ANNA LACEY
CONTRIBUTORS: TOM SANDERS
TERRY WILKIN
STEVEN ROBINSON
LUCILLA POSTON
PRODUCER:
NOT CHECKED AS BROADCAST
PORTER
Hello. Metabolic syndrome - or syndrome X as it was known when it was first identified in the late '80s - didn't even feature in the curriculum when I was at medical school. Yet just 20 years later, as many as one in four American adults has three or more of the cardinal features of the syndrome: namely
And where America leads, the rest of the developed world often follows:
CLIP
Since the 1970s the average UK adult has gained some nine kilograms in body weight and that's the average, there are many who have gained more. And that's not an increase in bone or water or muscle, that's an increase in body fat. One imagines there can never have been a time in evolutionary history when we have been the size that we are now.
PORTER
Nine kilos being one and a half stone.
With the exception of an expanding waistline, the features of metabolic syndrome are silent and easily missed - at least to start with.
CLIP
The vast majority of people with metabolic syndrome do not know they have it. They don't have symptoms, they don't realise that their blood pressure's high, their cholesterol's high, they are having risk of this damaging their arteries and maybe sadly first find out when they have a heart attack 15, 20 years later.
PORTER
My guest today is Tom Sanders, he's Professor of Nutrition and Dietetics at King's College London.
Tom, before I get you to explain metabolic syndrome, perhaps we should start off by saying why do we worry about it, why's it important?
SANDERS
It turns out that metabolic syndrome is a major cause of heart disease, particularly in people from South Asian origin, this is where I think where it first came to light. We couldn't explain the higher risk of heart disease in Indians and Bangladeshis, Pakistanis in terms of the usual risk factors, like cigarette smoking - they didn't smoke - or the higher blood pressure wasn't particularly high. And it turns out they had this syndrome which is - you can see it in terms of shape, we call it a martini glass figure, where you can quite often have thin arms, thin legs but a little pop belly. And it's the inappropriate storage of fat inside the abdomen and in the liver rather than in normal fatty tissue that seems to increase risk of heart disease but also diabetes. And it may also now increase risk of colorectal cancer and breast cancer.
PORTER
Now there are various definitions of the syndrome but all include a large waist, the pot belly you were referring to there, so if you're listening at home just jot these figures down and get the tape measure out. You're at definite significant risk if your waist is over 40 inches if you're a man, 34 inches for a woman, thresholds that drop to 35 and 31 inches respectively in Asians. And that's real measurements, not the size on the label on your jeans, which probably underestimates your real waistline by a couple of inches.
Tom, why is it that we doctors now are interested in waistline, is it because of this internal fat deposition?
SANDERS
Yes you can be fat and women - and healthy, I mean women are twice as fat as men and generally at a lower risk of heart disease, at least prior to the menopause. But if you store fat in the wrong place, particularly around the intestines, visceral fat, men quite often say this isn't fat, it's muscle - punch it.
PORTER
Solid muscle.
SANDERS
And that increases blood pressure, it has effects on blood lipids. Fat that's stored on the legs and round the hips seems to be relatively inert compared to this sort of fat.
PORTER
You say inert, what is this fat doing that's changing things?
SANDERS
We used to think of fat as just being an inert energy store but we now know that it's actually an endocrine organ, it produces hormones that signal back to the brain, in the normal situation it signals back to the brain and says stop eating and it burns up a little bit more energy. The fat deposits in the abdomen makes us less able to handle fuels like glucose and it can lead to higher levels of blood glucose and higher levels of blood fats.
PORTER
Now this is the content - you often hear the term insulin resistance and it's this fat that's causing that is it?
SANDERS
Metabolic syndrome is sometimes called insulin resistant syndrome, we need insulin to pump glucose from the blood supply into muscles so we can use it. If you come resistant to insulin the glucose stays at high levels in the blood and the high levels of glucose - and also you increase the levels of insulin to try and get the glucose out - cause damage to the arteries.
PORTER
Terry Wilkin is Professor of Endocrinology and Metabolism at the Peninsular Medical School, and heads up the ongoing EarlyBird diabetes study which hopes to identify factors that increase the likelihood of developing insulin resistance later in life. And, as he explained to our reporter Anna Lacey, the link with obesity is already very clear, and metabolic syndrome a growing problem - in more than ways than one.
WILKIN
I'm quite sure that the components of metabolic syndrome, all of them, counted separately or together, are on the increase. We deal with some of them quite effectively but the tide of change is certainly against us because the incidence with which these disturbances are occurring is rising, I mean one only has to look at the primary component amongst them, that of diabetes, to see what is happening.
LACEY
Jo Parke has been diabetic for 20 years and has many of the symptoms of metabolic syndrome, including high blood pressure, high cholesterol and excess fat around the waist. But in the early days while her symptoms were mild, doctors thought it was nothing more than a virus. It was only later when her condition became more serious that the diabetes was finally identified.
PARKE
I was feeling very tired, always thirsty, sick, sort of infections coming up all over my body it has affected my eyesight as well and I couldn't see.
LACEY
So at that point you were diagnosed with diabetes but at what stage did it move from just being diabetes to metabolic syndrome?
PARKE
Blood pressure problems actually came very, very quickly and the doctor that I saw said that all these things that were happening to me were connected to the fact that I was diabetic. So it was at that stage. So in the same year that I was diagnosed as being diabetic they picked up all the other symptoms that went with it.
WILKIN
I like to look at metabolic syndrome as a cartwheel with many spokes and those spokes are the various components. But at the hub is this notion of insulin resistance. If you can reduce the insulin resistance and weight reduction is the prime lifestyle intervention that will do that but there are medications that can help, the wheel will slow and the problems associated with those spokes will diminish. Cholesterol will go down, triglycerides, the fats will go down, risk of coronary heart disease will go down, blood pressure will go down and so forth.
LACEY
To find out more about who can be affected by metabolic syndrome I've come to St Mary's Hospital in London to speak to consultant physician and senior lecturer in endocrinology Dr Steven Robinson.
ROBINSON
Most of the patients do have increased weight but the problem is not so much with weight and obesity but it seems that carrying too much fat around the waist seems particularly important and that certainly seems important for example in the difference in different ethnic groups - some people tend to carry more weight around their tummy which gives them that increased risk. Indian Asians have the greatest risk, even for a given weight.
LACEY
Medication can reduce both the current symptoms and the risk of heart attack in the future. But many people are never even diagnosed.
ROBINSON
The vast majority of people with metabolic syndrome do not know they have it. They don't realise that their blood pressure's high, their cholesterol's high, they are having risk of this damaging their arteries and maybe sadly first find out when they have a heart attack 15, 20 years later.
LACEY
So do you think that people should be going to the doctors to try and become diagnosed?
ROBINSON
I think we need to be aware of all health risks in this country, I don't think people need to go to the doctor particularly because of concern of metabolic syndrome. But many conditions are preventable and so yes I think an overweight person would benefit from going to their doctor, not only to think about risk of metabolic syndrome but a lot of conditions.
LACEY
New syndromes can be highly controversial, and metabolic syndrome is no exception. It's said by some that the rise in cases is a result of doctors being better at spotting it and a consequence of the high profile given to the obesity epidemic. However Terry Wilkin strongly disagrees.
WILKIN
I don't think it's anything to do with profile or awareness or focusing more, I think there is a real increase - I mean the well documented increase in body mass, in obesity, in high BMI - however you wish to define it - with that there is a well documented increase in insulin resistance, which is the basic issue we're talking about, and with that there is well documented increases in high blood pressure, in high cholesterol, in high blood fats and so forth. I think it's a reality.
LACEY
But even though the effects are real, Steven Robinson says that some doctors, himself included, are reluctant to describe the symptoms as metabolic syndrome.
ROBINSON
I tend not to use the phrase with patients, I personally tend to talk about each individual risk and addressing each individual risk and how they can work together. But each clinician has their own technique for trying to warn people of risk and sometimes the diagnosis "metabolic syndrome" may be useful to a patient for them to hang their coat on and see that it's an issue. So different clinicians may address that differently.
LACEY
But seeing as it is on the increase do you not think it might be useful for there to be some kind of consensus across all doctors so that people, wherever they live or whoever their doctor is, will have the same diagnosis wherever they go?
ROBINSON
I think that may be useful if it were to happen, I don't see a consensus coming on the metabolic syndrome and, for example, it's different in the United States as the United Kingdom but I don't think the risks are different. So unfortunately I see consensus may be further away rather than closer.
PORTER
You are listening to Case Notes, I am Dr Mark Porter and I am discussing metabolic syndrome with my guest Professor Tom Sanders.
Tom, why do some people lat fat around their midriff or around their guts?
SANDERS
Some of it's hormonal, some of it's genetic and some of it may be acquired through early life experience, so whether their mother had diabetes in pregnancy may increase risk. We know that, for example, the group that's very much at risk are people who have been sportsman - like footballers - and then they stop playing sport and they tend to put on fat round the abdomen more than anywhere else.
PORTER
We talk about middle aged spread and the sort of pot belly, particularly the man, is it something that - obviously it develops with age, you're more likely to get it in middle age than at any other time?
SANDERS
We tend to think of sort of beer belly particularly in men and beer drinking associated with the sort of apple shaped obesity. And as you get older you probably become - less exercise, less activity, there are also probably hormonal changes - the rate at which we burn up energy - goes down, so when you get to 50s or 60s you need much less food energy than you do in your 20s, probably a third less.
PORTER
When Tony Russell's doctor diagnosed metabolic syndrome his initial reaction was one of relief - could it explain why he was finding it so difficult to control his weight?
RUSSELL
It was about 10 years ago I went to the doctors, I couldn't work out why it was that I was eating fairly healthily, going to the gym everyday and yet I couldn't lose an ounce in weight.
PORTER
And your weight at the time was what?
RUSSELL
It was about 104 kilos.
PORTER
A hundred four kilos, so that's heavy and how tall are you?
RUSSELL
I'm 5 foot 11.
PORTER
Not tall enough for 104 kilos. And that weight was collected where?
RUSSELL
Around the middle mainly.
PORTER
And what did you think was going on?
RUSSELL
Well I - you know I couldn't understand it, because all my adult life up until then I'd weighed like 11 stone and then I was ill with depression for a year or so and then the next thing I know I'm 104 kilos.
PORTER
So you went along to see your doctor and what happened then?
RUSSELL
I had a whole series of blood tests, urine samples, glucose tests and that kind of thing. My first GP he said your triglyceride levels are high but I wouldn't worry about that but I persisted and I asked to see an endocrinologist and it was the endocrinologist that told me I was insulin resistant and had metabolic syndrome.
PORTER
Was that the first time you'd heard the term?
RUSSELL
Yeah, I didn't - I'd never heard of it before.
PORTER
And how did the specialist explain it to you?
RUSSELL
Well that's interesting Mark because he said - he said if I'd been born in Stone Age times I would be all well set because my body's extremely efficient at storing fat. Which is an interesting way of putting it.
PORTER
Not what you want to hear in the 21st Century.
RUSSELL
No exactly.
PORTER
So the approach - and what features of the syndrome did you have?
RUSSELL
Well it's like I said I can't lose weight and I couldn't work it out, I'm not a couch potato, I don't drink beer and I don't sit around eating doughnuts. My triglyceride levels were 24.
PORTER
That's very high.
RUSSELL
Yeah that's what the endocrinologist said.
PORTER
And did you have high blood pressure, diabetes?
RUSSELL
Not diabetes, no. My blood pressure, every now and then they connect me up to a machine for 24 hours to monitor it and they don't seem too concerned when they do that but whenever I have it done like a one off in the GP practice it's always high.
PORTER
So having metabolic syndrome has meant what for you and how are your doctors treating it?
RUSSELL
I have a highly concentrated fish oil, I take a statin, I'm not a very good patient for a doctor because I won't take the other medication that I'm supposed to take.
PORTER
But one of the basic tenets of it is to try and control the weight and alter your diet, what have you done on that front?
RUSSELL
Well I, as I say, I eat very healthily, my wife Angie really looks after me you know, to me she's a world expert on this condition because she cooks very healthily for me. But - I live in this weird world where things that would normally be considered healthy for people, like bananas for example, or like if you're on a diet people eat jacket potatoes and that, things like that are not healthy for me.
PORTER
So Angie who does the cooking in the house?
ANGIE
I actually do the cooking in the house.
PORTER
So you're in charge of Tony's diet then?
ANGIE
I am very much so.
PORTER
And how's that changed since he's been told he has metabolic syndrome?
ANGIE
It's been quite difficult because in the past I've always cooked reasonably healthily but what I hadn't managed to do was to cut portion sizes down, whereas what I've learnt is most healthy for Tony now is to have little and often really so that his blood sugar doesn't spike during the day.
PORTER
And the general advice that Tony's been given is that he should go on to a lower carbohydrate diet, what practical differences has that made for you?
ANGIE
It's meant I need to use more basic products really, I always use wholemeal flour, always wholemeal bread if he has bread at all now, anything that his body would find a lot harder to digest is what I now need to give him really, so his body has to work harder at it. I also use sweet potatoes as well rather than the normal variety.
PORTER
So you're looking for foods with a lower glycemic index, is that something you've found easy from the labelling etc?
ANGIE
Not from the labelling, lots of research has helped though.
PORTER
What did the professor tell you about the long term implications of having metabolic syndrome?
RUSSELL
Well it's not good is it. What adds to my problem is that I've a history of stress, anxiety and depression. And when I get depressed I tend to stop exercising and not be so careful about what I eat. So you know people have a lot worse problems than me and I wouldn't want to be over dramatic but this is a condition that I could do without having, I'm well aware that a 40 inch waist is not good for a 52-year-old man.
PORTER
Tony and Angie Russell talking to me earlier.
Tom Sanders, Tony is convinced that his metabolic syndrome makes it difficult for him to lose weight, as we heard there - a conviction I must say that's shared by many of my patients - but is there any science to support that? Is abdominal fat any more difficult to lose than fat elsewhere?
SANDERS
Well one of the features of metabolic syndrome is high levels of insulin in blood and insulin is actually - makes people feel hungry and it's very difficult quite often for people with type 2 diabetes to actually lose weight, so they feel hungry a lot. What we do know is that the key to controlling metabolic syndrome is to lose a little bit of weight, it doesn't have to be a lot, and increasing physical activity. That doesn't necessarily mean to say going to the gym, taking exercise, but it's things like brisk walking, walking up and down stairs instead of taking the escalator, doing at least 30 minutes a day is the sort of figure which seems to be the threshold. A lot of people only do 30 minutes a week in the UK. So you don't actually have to have huge changes, if you can lose a bit of weight, that means cutting down on fat, cutting down on unnecessary additions of things like sugar to foods ...
PORTER
You say a bit of weight, I mean Tony was about 16, 17 stone, what sort of level of weight are we talking about?
SANDERS
Even losing half a stone or a stone will make a big difference, you haven't got to get - ideally he should be down around about 12 stone but even just losing half a stone or a stone, provided it's not done too quickly, is helpful.
PORTER
Because a lot of people start trying to lose weight and then they don't make a big inroad into it so they sort of give up but you're saying any step is a step in the right direction?
SANDERS
Any step because what's going to happen if he doesn't do anything he's going to go from 16 stone to 17 stone and the fatter people get the worse their control of blood pressure and all those other things. We know if you lose about a kilogram of bodyweight your blood pressure goes down by about a millimetre of mercury.
PORTER
Does it make any difference which sort of diet you follow, we were talking there about a low GI diet, perhaps you could explain what that is and is there any science behind using that to help people with abdominal fat?
SANDERS
Well a low GI diet is one that leads to fewer spikes in your blood sugar levels and ideally it's carbohydrate that isn't very rapidly absorbed. It isn't a simple differentiation between sugar and starch and some starchy foods are better than others, so basmati rice is better than ordinary long grain rise, it's slower; pasta is better than bread and it doesn't really matter whether it's white bread or wholemeal bread, they're both - they're quite high GI ones. What is better though is bread with bits in it - sort of multigrain bread seems to slow down the absorption.
PORTER
And how GI foods, very high GI foods, will presumably be confectionary and things like that - raw sugar in biscuits and cakes ...
SANDERS
Yeah will sugar is but actually you know boiled ordinary white rice or potatoes - mashed potatoes - very high GI. It does depend how you cook them, how they're processed. So if you take something like fruit - fruit is not such a high GI if you crunch away at it but if you liquidise it and consume it as a smoothie then it's a high GI. So what you're trying to do is get the glucose that comes from breaking down starch is released into the blood quite slowly so you don't get high levels.
PORTER
And does that have an effect, if you're following a diet calorie for calorie is a low GI diet likely to help you lose more weight, more quickly, in this situation - any evidence to support that?
SANDERS
Well we've been doing a very big study sort of addressing this question in people who've got metabolic syndrome and all I can say we don't find any different in the ability to lose weight. But it does help them a little bit with controlling their blood/fat levels.
PORTER
I should of course mention that one of the ways of medical approaches to metabolic syndrome is to use drugs to lower high blood pressure, cholesterol lowering drugs and tight control of sugar levels but going back to this thing about losing weight, that's one of the key tenets to dealing with metabolic syndrome.
SANDERS
Yeah, I mean I think people really need to watch when their waistline starts to go up, rather than buying a bigger waistband of jeans or letting your belt out, your belt is a very good reminder that you're getting porky around the middle.
PORTER
And we talked about 40 inches for men, for example, but you're actually saying the problem's starting way before then.
SANDERS
I think way before, I think a lot of people would say 38 is the high side. A healthy waist is probably between about 32 and 34, so even if you're getting 36 you know you should be ...
PORTER
Ok, well we've talked about the consequences of weight gain in later life, but what about at the other extreme? Can weight gain influence our future health even before we are born? Lucilla Poston is Professor of Maternal and Foetal Health at King's College London, and has a special interest in the impact of a mother's weight on pregnancy, and on the long term health of her baby.
POSTON
The figures are pretty horrifying. As many as one in five women are what we call clinically obese in the United Kingdom now and the problem is that the evidence suggests that it's going up and up. So we have an increasing problem.
PORTER
So these are women who've already got a weight problem before they arrive at their first booking in appointment with their midwife or whoever and they then likely to gain even more weight during the pregnancy.
POSTON
Yes and I think most women feel they should be eating for two and that's absolutely not what they should be doing, particularly if they are a bit overweight to start with. We in the United Kingdom don't have an ideal weight gain for pregnancy and we don't recommend it because it's difficult to judge what's actually best for the woman.
PORTER
But an average weight gain would be what?
POSTON
Be 15-20 pounds, something like that. But there is recommendation in the United States that if you start off overweight then you shouldn't put on that much, we wouldn't recommend that but you know the whole - the whole idea is not to put on too much weight, to be careful about what you eat, particularly careful about what you eat when you're pregnant.
PORTER
What are the implications for mother and baby if mother is overweight?
POSTON
The implications are very considerable and I think most people don't appreciate how much they're putting themselves at risk by being overweight in pregnancy. We've done a recent study which suggests that people don't really have any idea that they are at risk and the problems that we see routinely are diabetes, people develop diabetes in pregnancy - it's called gestational diabetes - and they're more prone to that if they're overweight. Pre-eclampsia goes up as the woman's body mass index, her obesity index, goes up. People have more risk of haemorrhage, post-partum haemorrhage, if they are overweight. Nearly every complication we know about in pregnancy occurs more - with more frequency in women who are obese.
PORTER
Is there something about the type of fat that's laid down during pregnancy that's different from any other period?
POSTON
We don't know that and that's actually a very interesting question because different sorts of fat are different, as I'm sure you know. But central obesity is what we're worried about and certainly women who put on weight abdominally, so it may be that's particularly bad fat but we don't know that.
PORTER
What about for her baby?
POSTON
Well there are increasing worries about the child because we know first of all that the baby's likely to be born too big and that has its attendant problems - caesarean sections being more frequent if the babies are too big. There is a direct link between a mother's size and the size of the child, particularly with women who are really overweight. Paradoxically overweight women can also have very small babies, if they develop placental disease, so you get a lot of birth weight at both ends of the spectrum.
PORTER
And that link between weight is mediated how?
POSTON
The link with high birth weight is mediated by glucose, so a mother who is overweight tends to have a higher blood glucose concentration, that will get across the placenta, that serves to drive growth in the foetus directly and the baby's likely to be too big as a result of that.
PORTER
And are there any longer term implications, if you're in an environment where there's a lot of glucose, for instance, and mother's overweight does that implications for your long term health?
POSTON
Well that's my particular research interest and we are getting very worried that whilst the babies are put at risk by being born large that the large baby and the fatter baby may also grow up into an obese adult. And just because it's suffered this experience in the womb of the obese environment of the mother. So we're thinking that the mother's glucose or the mother's high insulin or indeed a hormone called leptin, which is associated with obesity, might in some way programme the child to become obese and that could be directly through having too much fat, to start with, but we also think it may actually be working on the brain of the developing child, which is very prone to change in structure and so on, obviously if the child is developing, that these hormones could permanently change the way the brain is wired and actually change the appetites of the child. So we've found in animal studies that obese mice have offspring who grow up obese and that's because they're eating a lot because their appetite has permanently changed.
PORTER
Because of course one of the theories has been historically in the UK that you have obese parents and therefore you adopt their eating habits, there's an environmental influence, but you're saying there's actually probably some pre-programmed ....
POSTON
Yes and of course in human studies it's very difficult to dissect out the environment the child is born into, in terms of nutrition and the exercise and the effects in utero.
PORTER
So where are we at that level - where are you in your research at the moment in terms of looking at real children?
POSTON
Well at the moment there are quite a few studies coming through which are suggesting that the child of an overweight mother could develop into an overweight adult but they are still in their infancy, we can't categorically say that at the moment. And so we're planning a very large study in the United Kingdom where we're going to recommend that obese ladies adopt a low glycemic diet - and that's a diet which has less - slow release glucose, not necessarily a reduction in calories but a lower glycemic index, bit more exercise. And so we're going to randomise women to a normal pregnancy diet and to our special diet and exercise and hope that we might be able to reduce the problems in the child and then we'll follow those children up. So we'll have an idea about the intervention and whether it actually works.
PORTER
Following them through until adult life?
POSTON
Through until adulthood yes.
PORTER
Lucilla Poston on why pregnant women shouldn't necessarily eat for two.
Tom, are there any warning signs that an otherwise apparently healthy person might be more likely to go on to develop metabolic syndrome? Lucilla mentioned gestational diabetes there, that can be a risk factor?
SANDERS
Yeah, I mean if the mother's had diabetes it means the offspring are more likely to get metabolic syndrome but it's not inevitable providing you keep their weight down and take exercise. The other thing is your family history - if you've got siblings or parents who develop diabetes at an earlier age - in their 40s or so - you need to be particularly careful to avoid weight gain and to make sure you take regular exercise. It is avoidable. In some quite nice controlled intervention styles showing that lifestyle change is the most effective to prevent it and it means keep an eye on your weight and taking regular exercise, I can't over emphasise the importance of exercise of keeping metabolic syndrome at bay.
PORTER
And if you start you must keep it up otherwise you become like one of those footballers ...
SANDERS
You've got to do it everyday.
PORTER
Tom, we must leave it there. Professor Tom Sanders, thank you very much.
If you want more information on metabolic syndrome, you will find some useful links on our website bbc.co.uk/radio4 - where you can also sign up for the weekly Case Notes podcast. Or you can call our Action Line, if you don't have access to the internet, on 0800 044 044.
Next week's programme is all about side effects. Why natural doesn't necessarily mean problem free. How common does a side effect have to be to make it onto those scary leaflets now found in all prescribed medicines? And who watches over new drugs to protect us from another thalidomide disaster?
ENDS
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