When Professor Sir Michael Marmot was a junior doctor he decided that medicine was failed prevention.
To really understand disease you have to look at the society people live in. His major scientific discovery came from following the health of British civil servants over many years. The Whitehall studies, as they're known, challenged the myth about executive stress and instead revealed that, far from being 'tough at the top', it was in fact much tougher for those lower down the pecking order. This wasn't just a matter of rich or poor, or even social class. What Marmot showed was the lower your status at work, the shorter your lifespan. Mortality rates were three times higher for those at the bottom than for those at the top. The unpleasant truth is that your boss will live longer than you.
What's more, this social gradient of health, or what he calls Status Syndrome, isn't confined to civil servants or to the UK but is a global phenomenon. In conversation with Jim Al-Khalili Michael Marmot reveals what inspires and motivates his work.
Extracts from interview conducted by Jim Al-Khalili (JK)with Michael Marmot (MM)
MM: Definition of epidemiology: The study of disease and the distribution of disease in populations and the determinants of that distribution. Now applied to non-communicable disease, to mental illness, to accidents.
JK: And is it [epidemiology] something that can tell us more about the individual.
MM: Well, a lot and a limited amount. By that I mean we know that if you eat a certain kind of diet, everybody who eats that diet, on average, is likely to be healthy compared to those who don’t. It doesn’t necessarily tell each individual the determinants – the reason why you’re healthy and someone else isn’t might be because you are genetically different; but in general it says quite a lot about the conditions affecting your risk of illness.
JK: So coming back to the Whitehall Study, what did looking at the grades of civil servants tell you?
MM: To my amazement and to the amazement of everybody I showed these data to, and initially disbelief, we found the lower the status, the higher the risk of heart disease. But it wasn’t just mortality from heart disease it was mortality from a whole range of diseases. So that the lower the status, the shorter the length of life. So in a study without the richest and without the poorest we showed the lower you were in the hierarchy the higher the chance of dying of heart disease – step by step down the gradient. So the top level civil servants had the lowest risk of dying from heart attacks; the next level down somewhat higher, the next level down higher still – it was a social gradient from top to bottom.
JK: And that’s what’s so surprising, because you would think that anyone above a certain salary level should have a similar life expectancy and levels of disease. So the idea that this kept on changing continuously all the way to the top was quite revolutionary.
MM: It was, if you like, revolutionary, certainly very challenging to understand. So then we had to think, well if it’s not poverty, it’s something to do with your status. What is it about your status that can have this profound [impact] – it’s not subtle, it’s life and death – it’s having a profound impact on people’s health?
JK: There’s something else going on.
MM: And that’s why I set up the Whitehall 2 study.
JK: So Whitehall 1 – you found there was this smooth gradient going all the way from the bottom to the top of the Civil Service structure. Whitehall 2 – what did you find?
MM: What I think Whitehall 1 led me towards was that what goes on in the mind is very important for what goes on the rest of the body. So we talk about psychosocial processes, how social influences affect the mind and how that in turn affects other parts of the body to change the risk of disease. We studied the work environment, the idea that it’s not having a lot of demand by itself that is stressful. The high status person has a lot of demand, but he or she has a lot of control, and the combination of high demand and low control is what’s stressful. And then the idea was that would influence various biological pathways that would increase risk of cardio-vascular disease. And indeed, the data are imperfect, but we’ve got a lot of evidence supporting that.
JK: Michael, can you give me an idea of how the social gradient affects life spans of individuals?
MM: In the Scottish city of Glasgow, men in the poorest part of the Glasgow have life expectancy of 54; and in the richest part of Glasgow, 82.
JK: It’s incredible…
MM: Isn’t it incredible?
JK: So when we’re looking at the causes of stress, you’re saying it’s a combination of not being in control and having high demands on you. I’m thinking of a simple example here where I could try and prove the contrary. Imagine in a school the person manning the reception desk who just answers the phone won’t have much control, but that’s a pretty low-stress job when you compare it say with the head-teacher’s job where you have the control but presumably there’s lots of demands and lots of stress therefore on your time. Does that fit into your model?
MM: Yes, by and large it does. We distinguish between passive jobs, where there’s low demand and low control, and jobs where there’s high demand and high control, which in general in my own view, are the best ones. But I’m willing to predict that the times when head-teachers feel most subject to stress is when they think they’re subject to some higher authority [e.g. when] the government’s fiddling with their lives. In other words they’re losing the control that normally they have. Now the kind of job that you might think is a low-stress job but in fact isn’t, is when people tell you, “We weren’t allowed to talk to each other. We had to ask permission to go to the toilet or to get a cup of coffee.”
JK: They’re not in control…
MM: You’re not in control of even simple things…this is ghastly, the idea that your life is controlled to that degree.
JK: So they may not have the responsibility of someone higher up the structure of the organisation, but the fact that they have no control is far more stressful.
MM: And we showed that people with low control at work in the face of high demands and lack of support from supervisors and co-workers had higher risk of the so-called metabolic syndrome, which is a precursor to diabetes and a risk marker for heart disease. So we showed that the more occasions people had this stressful pattern of high demand, low control and low support, the more likely they are to have the metabolic syndrome, which is a precursor to diabetes and heart disease.
JK: Now this is what you call “Status Syndrome”. The extent to which you define someone’s status and therefore their life expectancy is very specific. There’s a study that says that someone with a PhD will live longer than someone with a Masters degree. Can you really say that someone with a PhD has more control than someone with a Masters degree?
MM: Well, Robert Erikson who did that study in Sweden, he said that it’s very interesting that in general the people with Masters or professional degrees had higher income than the people with PhDs because it included doctors and engineers, yet they had higher mortality than the PhDs. And his speculation was exactly the “Whitehall phenomenon”, that the people with PhDs could decide, “Wow, this is really interesting and I’m not going home tonight, I’m going to stick with this” and then, “Oh God, this experiment isn’t working – I’m going to walk round the lake.” And in his speculation, that’s what control means.
JK: I think it’s fair to say that not everyone agrees entirely with what you call Status Syndrome. Maybe by concentrating on stress you could miss straightforward causes of disease. For example, everyone thought that ulcers were caused by stress, but we now know that they are caused by a bacteria. Is there a danger that by trying to fit everything into this one box, that stress is the underlying cause of disease, we may miss other more subtle causes?
MM: Well, there’s always a danger of being sloppy and unscientific, and just simply lumping everything together under a stress rubric is very dangerous. And it’s very constructive to have people say they disagree with you. But don’t just simply say because we got it wrong with peptic ulcer 30 years ago ergo your data showing that the metabolic syndrome is related to psychosocial processes in the workplace must be wrong is unscientific. To say we now know that ulcers are caused by infection is missing the fact that the h-pylori infection is very common.
JK: H-pylori is the bacteria that is the underlying cause of ulcers, but you’re saying that there could be other reasons as well that bring about …
MM: Of course. Most of us have h-pylori infection but most of us don’t have peptic ulcer. So we know the cause of lung cancer is smoking but we also know that most smokers don’t get lung cancer. So there are other things going on. Now in the case of lung cancer and smoking, all our efforts to reduce smoking have led to this social gradient in smoking. So now it’s a slightly more complex issue: how do we deal with the causes of the cause which leads to the social gradient?
JK: But if you accept that it’s lack of control over our lives that makes us ill, shouldn’t it then be the individual’s responsibility to take control of their lives?
MM: Of course. But we’re not all equally given the conditions that allow us to take control of our lives. If you’re leaving school with five ‘Cs’ or less at GCSE, and there’s an economic downturn and just under one million 18-24-year-olds are unemployed, how can you take control of your life? It’s not your fault there are no jobs around. So yes, finally, ultimately, I would like everybody to be in the position where they can take control over their lives. But we’ve got to get the conditions right.
JK: There will people who will say you’re talking about the nanny state, an interventionist state that tries to…people can’t empower themselves…
MM: If you think it’s the nanny state to provide a good education system, well go ahead. I wouldn’t say that’s the nanny state. I would say that we’re failing children on a grand scale – we’re not giving them the resources to be able to take control over their lives! That’s anything but the nanny state! That’s what I would want any state to deliver – a decent education system. Now we know the performance in GCSEs isn’t just due to what goes on in schools. The quality of early childhood development is key. If you want to reduce inequalities in early childhood development, you’ve got to reduce inequalities in society. I don’t think that’s the nanny state. If the nanny state said you can’t play rugby because you might get injured – that is the nanny state.
JK: Clearly a lot of different issues and factors have to be considered together here, but how do you go from scientific evidence to policy and what motivates you to do so?
MM: I started doing this because I was really interested in the scientific question. Then one thing led to another – we published hundreds of scientific papers, richly rewarding, very exciting, feeling you’re making progress. But underneath it all is the question, what if somebody took this seriously? Couldn’t we do something about this to improve people’s lives? If you reach the judgement that we could make that social gradient shallower and we don’t do that, isn’t that rather unjust? Am I being hopelessly naïve?
JK: It sounds like (and it’s been quoted that this is what you do), you’re mixing ideology with evidence.
MM: The WHO Commission on the social determinants of health had been criticised as being ideology with evidence. I took that criticism as praise – I said we do have an ideology: health inequalities that are judged to be avoidable by reasonable means and are not avoided are wrong, they’re unjust, they’re unfair. And so our ideology is to do something about that. But the evidence really matters.
JK: You see now, it sounds admirable, and it’s certainly true that scientists should be more ethically aware of their moral responsibility of the research that they do across the whole of science. But there is the danger, certainly if you had ideology driving the scientific evidence, that somehow the science becomes less objective, however good and admirable and good those motives are.
MM: Yes, and I think that’s a real danger. But there’s also a danger in saying I’m a pure scientist and I don’t care if anybody takes this seriously or not. The area in which I’ve been labouring, which is really about public health, is about improving things. But we want the best evidence. I’ve tried to make my prejudice clear, my ideology I call it, not a prejudice.
JK: And now you’ve essentially entered the global stage with reports for the World Health Organisation, the European Union, looking at social determinants of health internationally. Do other counties show the same trends as you’ve found in the UK?
MM: What’s absolutely remarkable is that wherever we look we find a social gradient in health.
(A podcast of the entire interview is available on the BBC Radio 4 website under the programme title “The Life Scientific”.)
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