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INSIDE HEALTH

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Programme 5.

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TX:听 18.02.14听 2100-2130

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PRESENTER:听 MARK PORTER

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PRODUCER:听 PAMELA RUTHERFORD

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Porter

Coming up in today鈥檚 programme:听 Statins - Dr Margaret McCartney will be here to clarify cholesterol.听 How can you tell if you are one of the five million extra people in the UK that NICE believes could benefit from taking a statin?

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Air pollution - following new research linking heart attacks to particles in diesel fumes, we look at what we can do to protect ourselves.

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And treating a cough - why do so many people end up on antibiotics when the best evidence suggests that they don鈥檛 help in most cases, and may make matters worse?

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But first loneliness and reports in the media this week that being lonely in old age is deadlier than obesity. A claim that piqued our interest here at Inside Health 鈥� Margaret McCartney has been taking a closer look. Margaret, press coverage said being lonely was worse for you than being obese, were you happy with that comparison?

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McCartney

I think it鈥檚 very difficult.听 The problem with these studies is that they haven鈥檛 directly compared the impact of being obese with the impact of reporting that you鈥檙e feeling lonely.听 So I think it鈥檚 very hard to be clear what the risk is in proportion with other risks but I think we can be clear that it is a risk factor that is present and has been found of course in many different types of studies and it does seem to be persistent, so it鈥檚 not something that鈥檚 picked up in some studies and not in others, it is a fairly consistent research finding across the board, not just in the US but also in the UK.

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Porter

Loneliness is not good for you.

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Well we鈥檙e joined now by Christina Victor, who鈥檚 Professor of Gerontology and Public Health at Brunel University.听 Now Professor Victor does this come as any surprise to you?

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Victor

No not at all.听 As early as the 1980s people were noting the link between an individual鈥檚 social network and their whole range of health outcomes from mortality through physical health to mental health problems.听 So no it鈥檚 not particularly a surprise.

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Porter

Do we know what loneliness is doing, can you give me an example of the sort of pathway that it might affect your wellbeing and send you to an early grave?

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Victor

If we knew that we would be able to solve the problem rather easily.听 I think it鈥檚 rather complicated.听 Some studies have suggested that loneliness affects a number of physiological parameters such as blood pressure and a range of other biological markers which may increase people鈥檚 risk of heart disease or dementia but I think it鈥檚 not entirely clear.听 The other suggestion is that perhaps because people are lonely or detached from a social network they indulge in less healthy behaviours, such as they鈥檙e more likely to smoke or to be obese or to not take exercise or perhaps not consult their GPs.

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Porter

Is this effect limited to older people?

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Victor

Oh I wish I knew the answer to that, regrettably because we think that loneliness is particularly a problem with older people we haven鈥檛 really looked at how the effect of loneliness may impact upon young adults.听 Certainly in Britain there are two peaks for loneliness, one for young adults, let鈥檚 say 鈥� between the ages of about 18 and 25, then loneliness decreases as we might speculate because people are employed and married and have relationships and then there鈥檚 an increase in loneliness when we get to our 60s and 70s.听 So we鈥檝e looked at the effect of loneliness and a range of health outcomes for older adults but as far as I鈥檓 aware nobody鈥檚 done that for younger adults and that would be a very interesting question to answer.

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Porter

Margaret, of course another problem with this is defining what we mean by lonely, one man鈥檚 loneliness is another鈥檚 solitude.

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McCartney

Absolutely and I think it can be quite difficult in a research study to fully play out what it is that people are actually complaining of and I think one of the saddest things, as a general practitioner, you come across is being perhaps the only person to have had a conversation with someone for a week or two weeks or sometimes even longer, it鈥檚 not difficult to see why that鈥檚 very bad for people if they鈥檙e wanting company, needing company, really crying for social interaction and they鈥檙e really having very little or none of it and that 鈥� and perhaps their GP is the only person or a district nurse is the only person that鈥檚 providing that for them.听 So I think for my mind at least and what I see from day to day work there鈥檚 a huge well of loneliness out there that I鈥檓 sure has a huge impact on people鈥檚 wellbeing.

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Porter

And it鈥檚 not always obvious I presume Christina that somebody is lonely?

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Victor

No, I think it鈥檚 very difficult.听 There was a recent survey that was conducted which demonstrated that older people, if they did feel lonely, would be very reluctant to talk about it with their family and with their friends and I think it鈥檚 very difficult to identify people who are lonely just from ordinary daily life.

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Porter

Practically what should we be doing about this?

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Victor

Well that too is the $65,000 question.听 There are 鈥� first of all there鈥檚 a problem, as Margaret鈥檚 already alluded to, as how we define loneliness and the literature if beset with problems of studies purporting to measure loneliness but actually measuring social isolation and vice versa.听 So first of all it鈥檚 a rather difficult subject to pin down.听 And we have very, very limited evidence about what works.听 It certainly looks like group kinds of activities are the most effective against loneliness but really we don鈥檛 really understand loneliness enough to understand how to then intervene to remediate it.

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Porter

Professor Christina Victor thank you very much.听 And you will find a link to the presentation given in Chicago that started all this on the Inside Health page of the Radio 4 website.

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Now, statins and last week鈥檚 announcement by the National Institute for Health and Care Excellence (NICE) that it is considering lowering the threshold for using them to prevent cardiovascular disease.听

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NICE is proposing to reduce the existing cut off of a 20% or more chance of having a stroke or heart attack over the next 10 years, to just 10%. A move that could see as many as five million extra people in the UK being prescribed them.

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Might you be one of those five million and how can you tell?

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Margaret McCartney has been looking at the tools that doctors use to work out the odds of an early heart attack or stroke. And there are a few different ones aren鈥檛 there Margaret?

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McCartney

There are indeed.听 So we have in the UK quite a choice of risk calculators that we can choose from, although NICE have recommended that we use one called Qrisk2 and in Scotland we tend to use one called ASSIGN.

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Porter

And they鈥檙e basically doing the same thing these calculators aren鈥檛 they?

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McCartney

Yeah, they have similarities and differences.听 So you tend to 鈥� all of them want to know what age you are because age is the biggest risk factor at all, your gender, some will ask for your ethnicity because some ethnic groups have a higher risk of cardiovascular disease compared with others, whether or not you smoke, what your blood pressure is and there are further differences between them.

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Porter

And the idea is that they put all of these figures into an algorithm and it comes up with the magic figure.

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McCartney

Yes it comes up with an estimate.

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Porter

But that鈥檚 based on what, I mean鈥�?

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McCartney

Yeah this is interesting.听 So it鈥檚 based on look back data.听 What researchers have done is they have looked at the records and the case files of patients who have had cardiovascular disease and they鈥檝e tried to find out what are the things that make it best able to predict whether or not these people would have that event in their life.听 And what the risk calculators then try and do is work out looking forward if you can identify these people or not, try and work out which are the people in your population that are at higher risk of having a cardiovascular event like a stroke, a mini stroke, a heart attack.

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Porter

So essentially these calculators are based on what we鈥檝e learnt already and we鈥檙e trying to use that to predict the future.听 Is it any more accurate than trying to predict what happens to the stock market, how good it is 鈥� how good are these things?

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McCartney

It鈥檚 a really, really interesting question and I have to say that up until when I went to do some reading for this I was under the impression that they were pretty good.听 But actually they don鈥檛 work out terribly well.听 So a lot of the time they will identify people at being at high risk or higher risk when they鈥檙e actually not and they will also miss some people.听 But they tend to over-diagnose or over-calculate risk for a group of people rather than under-calculate risk.

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Porter

But that鈥檚 understandable isn鈥檛 it, if you鈥檙e going to err you would want to err on the side of caution I suppose, you wouldn鈥檛 want to false reassure people who could be at high risk.

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McCartney

Of course, of course but we live in shifting sands because over the last 20 or 30 years actually the rate of cardiovascular disease has actually been in decline, so we鈥檙e constantly trying to predict the future but using evidence that we鈥檝e got that鈥檚 been generated in the past.

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Porter

One of the things that intrigues me Margaret is that exercise doesn鈥檛 seem to feature, certainly not in the Qrisk calculator that I use and yet you could be sitting with somebody with a high cholesterol, for instance, and they鈥檙e 55 with a high cholesterol, they鈥檙e in the at risk group but they鈥檙e a marathon runner!

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McCartney

And the same for diet as well and I think part of the problem is that these algorithms have been generated from data that鈥檚 available in your medical records, so if you鈥檙e not recording and we don鈥檛 routinely record how much exercise most of our patients are taking or what kind of diet they have this is not the kind of information people are going to be able to work with.听 So we end up in a situation 鈥� we鈥檝e got a patient who is different from all your other patients but we鈥檙e trying to apply population data to.听 So population data鈥檚 great at telling you about a population but not so great at trying to predict what will happen to that one individual person.

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Porter

And that鈥檚 the problem with looking at an individual patient isn鈥檛 it Margaret, that actually there鈥檚 no such thing as an average patient, he or she may get no benefit and all the downsides.

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McCartney

Yeah and the lower the risk you are the bigger the chance there will be of you having no benefit but all of the potential side effects.

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Porter

A lot of people might think that the worst thing that can happen with a statin is it doesn鈥檛 actually offer you much protection against stroke and heart attack but there are significant side effects too.

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McCartney

Yeah and it鈥檚 really interesting when it comes to side effects from statins.听 A lot of papers have looked at the evidence and decided that actually the side effects are fairly minor and they鈥檙e short-lived and people make too much of them but in the real world and especially when you talk to other GPs it鈥檚 a really common scenario that people come in and they say I don鈥檛 feel well on a statin, some people will complain of muscle ache such that they can鈥檛 exercise, which is a kind of self-defeating thing if you鈥檙e trying to lower someone鈥檚 cardiovascular risk.听 All kinds of what some people might class as minor side effects but to a person who is taking it for something that they probably won鈥檛 get it becomes quite a major side effect.听 And then there鈥檚 the other things much rare but they do exist and it鈥檚 a slightly increased risk of developing diabetes because of the statins, slightly increased risk of having a kidney or a liver injury because of the statins.听 So there are lots of little things and the problem is that once you start to apply more and more medication to more and more people who were never going to die of the thing that you鈥檙e trying to prevent it becomes more and more difficult to say to those people you鈥檙e definitely getting a benefit if all they鈥檙e telling you that they鈥檙e experiencing is side effects.

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Porter

People are often surprised when I ask them for their postcode, can you explain the rationale behind that?

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McCartney

Yes.听 Yeah and again it鈥檚 trying to find out how can you make your calculator the best calculator for predicting who鈥檚 going to get cardiovascular disease before everyone else.听 So it鈥檚 generated by postcodes and that postcodes are a marker for deprivation and we know that deprivation is a risk factor for early cardiovascular disease.

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Porter

Because people often think it鈥檚 all about my cholesterol level but it鈥檚 not.

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McCartney

No, I think cholesterol鈥檚, in the grand scheme of things, actually quite a minor problem when we鈥檙e talking about risk and of course the biggest risks are age and again another really big risk that can be modified is smoking.听 And another big risk that can be modified is exercise.听 And instead we have a very medicalised approach to reducing cardiovascular risk which I think is a real shame.

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Porter

Thank you Margaret.

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And there is a link to our preferred calculators on the Inside Health page of the Radio 4 website if you would like to try them for yourself.

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Time now for some feedback.

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Last week鈥檚 item on glucosamine, following the release of new guidance from NICE saying that it had no place in the treatment of osteoarthritis, raised a few hackles.

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Bob Watson, among many others, says it does work 鈥� at least for him 鈥� and Maria Budd says she has seen it work in dogs so there must be more to it than a placebo effect.

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Please don鈥檛 shoot the messenger. All we did was point out that the very best trials show glucosamine isn鈥檛 an effective treatment for arthritic joints. Which was why NICE does not endorse it.

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And while I am no expert, both owners and vets are subject to the influence of the placebo effect. That is why the best trials are double blinded, neither recipient, nor observer knows who is getting what.听

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On a happier note, our report on new research suggesting that doctors should listen to their gut feelings prompted this e-mail from Sylvia Larrad:

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Sylvia Larrad

I am that patient that Margaret McCartney referred to.听 On my first visit to a new GP in Dorset, having just relocated from Manchester, I truly believe I owe my life to the GP who listened to my then scant symptoms and later, after confirmation of bowel cancer diagnosis, admitted he followed his gut feeling.听 This was all 14 years ago now.听 We all get gut feelings in many walks of life 鈥� I鈥檓 living proof that the system should allow them to be acted upon.

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Porter

If you want to share your thoughts, or suggest topics for us to look at, please do get in touch via insidehealth@bbc.co.uk

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Now close your eyes and imagine a GP鈥檚 waiting room. What do you hear? A hushed conversation, phones ringing, perhaps a child crying 鈥�.. and definitely someone coughing!

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Acute short lived coughs, typically caused by self-limiting viral infections that get better on their own, make up a huge proportion of a GP鈥檚 workload, even though we don鈥檛 have anything that can cure them. So why do so many people - like this chap end up on antibiotics?

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Actuality

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Cough patient

I started feeling unwell on New Year鈥檚 Eve and I was pretty congested in my head, started to cough and I could feel that my chest was getting a bit heavy.听 I let it go for about a week, called the GP up and her diagnosis was I had a chest infection and she gave me some antibiotics.

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Hay

My name is Alastair Hay, I鈥檓 a GP at Concorde Medical Centre in South Gloucestershire and I鈥檓 a Professor of Primary Healthcare at the University of Bristol.听 Cough is the most common presenting complaint to the NHS and to health services internationally.听 So this is bread and butter for GPs and nurses in the NHS.

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Porter

And you鈥檇 think that if it鈥檚 one of the most important conditions that we鈥檙e treating that we鈥檇 know how to treat it, are we there?

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Hay

I don鈥檛 think we are yet.听 I think we鈥檙e making great inroads but despite its frequency and despite how long we鈥檝e known it鈥檚 around there鈥檚 still quite a lot yet to do.听 It鈥檚 reasonably clear that the vast majority of people, probably of the order of about 80% who are presenting with relatively short-lived coughs that are associated with other respiratory infection symptoms probably won鈥檛 benefit from an antibiotic.

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Porter

What鈥檚 causing the majority of these coughs?

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Hay

Well that鈥檚 perhaps the first good question.听 So clearly we know that viruses and bacteria cause respiratory infections in both children and adults and we鈥檝e got some sense of the fact that some viruses are more common, for example things like respiratory syncytial virus are more common in children, other infections may be more common in adults.听 But most of the characterisation of the causes of cough have been done in more unwell patients who are in hospital and we know less than we should I think about the causes of cough in primary care.

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Little

My name鈥檚 Paul Little, I鈥檓 a National Institute of Health Research senior investigator and professor of primary care research at the University of Southampton.听 Even if you find a bacteria there most people will get better from bacterial infections anyway.听 So the viral bacterial thing is important but it can be overplayed a little bit because bacteria doesn鈥檛 equal I have to have antibiotics and similarly virus doesn鈥檛 necessarily mean you should never have antibiotics.听 And most people who still come to their GP will get an antibiotic now still, despite the evidence that antibiotics don鈥檛 work terribly well.

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Porter

That does surprise me slightly in that this message has been 鈥� well as long as I鈥檝e been a GP we鈥檝e been harangued for over-prescribing of antibiotics and in particular in coughs saying that actually most people who cough don鈥檛 need antibiotics.听 Are we prescribing fewer antibiotics?

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Little

No that鈥檚 one of the slightly worrying things, we seem to be doing fairly well at the end of the 鈥�90s when there was a reduction in the volume of antibiotics prescribed in the UK, down to the early 2000鈥檚 but since then there鈥檚 been a progressive rise in the volume of antibiotics prescribed.听 Now that鈥檚 not just the number of prescriptions, it鈥檚 actually also people are prescribing higher doses, so it鈥檚 not quite as dark as it looks.听 But we haven鈥檛 made much headway since the early 2000s.听 The problem is there probably are a few people who benefit from antibiotics and they are by and large people who have pneumonia and the question is can you easily pick up pneumonia?听 And the answer is 鈥� actually the good news is when it鈥檚 barn door you can but the subtler signs of pneumonia are often difficult to pick up and a GP will sometimes examine somebody and say don鈥檛 think you鈥檝e got pneumonia when there鈥檚 a little bit there.听 Does that matter?听 I think for most people it doesn鈥檛 matter actually, a tiny little bit of pneumonia that you can鈥檛 pick up as a clinician probably will settle by itself in most individuals.

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Porter

Another thing that patients often worry about is the stuff that they鈥檙e coughing up 鈥� Dr I鈥檓 coughing up nasty looking yellow/green stuff 鈥� is that of any significance?

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Hay

Just green phlegm on its own no.

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Porter

And that will be a surprise to most people because it鈥檚 one of the first things you hear from patients, isn鈥檛 it 鈥� I鈥檓 coughing up some nasty stuff?

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Hay

Absolutely and I think it鈥檚 quite nice if we can to sort of turn that round on its head and say well what are the positives about that?听 You鈥檙e clearing the phlegm from your chest, that鈥檚 probably a good thing, better than it sort of staying down in your lungs, that鈥檚 probably going to clear away the muck that perhaps otherwise could lead on to a more severe chest infection.听 So the cough is a healthy natural response and the clearing of phlegm is a good thing and we should expect it to last three, sometimes even four, weeks and so long as it鈥檚 improving and we鈥檙e not sort of deteriorating and we鈥檙e not experiencing other markers of severe illness then that鈥檚 perfectly okay and perfectly natural.

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Porter

What about temperature?听 People come in with chest symptoms we take their temperature, if it comes back high does it affect our management or should it affect our management?

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Hay

I think here we鈥檙e largely in the realms of absence of evidence, I think that all of us 鈥� patients and doctors 鈥� are concerned when there鈥檚 a particularly high temperature measured, by high I鈥檓 thinking of sort of greater than 39 or certainly once you鈥檙e getting into the 40 degree Celsius.听 And the thinking there is that that may be linked to a more severe chest infection like a pneumonia.听 But actually when you look at the evidence it鈥檚 really difficult, there鈥檚 very little evidence to suggest that even a very high fever means you should have an antibiotic.听 I certainly think that you should be seen by your GP but that doesn鈥檛 necessarily mean your GP should give you an antibiotic.

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Little

There鈥檚 a modest individual dis-benefit by having antibiotics.听 A. you鈥檒l encourage the resistant bugs to multiply in your throat and in your passages but you鈥檒l also have got rid of some of the good bugs that sit around in those passages that actually act as a protective way.听 You will also by getting antibiotics in early you鈥檒l stop an immune response that is actually helpful the next time you see it.

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Porter

Do we know looking at duration, because it seems to be important to patients, is that an indicator of it being more likely to be a bacterial infection that needs treatment or not?

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Little

No it isn鈥檛 is the short answer, in fact we鈥檝e done a recent very, very big trial across Europe and one of the groups you鈥檙e interested in was people who had longer [indistinct word] duration and they certainly don鈥檛 benefit from antibiotics.听 If anything it鈥檚 the other way round 鈥� people who get very sick quickly and come in quicker perhaps marginally more likely to benefit but only marginal and in fact the natural history of this illness is a very long one, it鈥檚 around three weeks for the people that we see and that鈥檚 an average, so 50% of people that we see will have a cough for longer than three weeks.听 So one of the keen messages to get across is actually this is a long lasting illness, you鈥檙e not going to feel great with it, we can鈥檛 do magic things, it will get better but it鈥檒l take a while.

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Porter

Professors Paul Little and Alastair Hay.

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And from viruses and bacteria, to something else that might make you cough 鈥� air pollution. 鈥淧ea souper鈥� smog may be a thing of the past, but less visible pollution is still exacting a toll on the health of commuters and city dwellers. And it鈥檚 not just our lungs that are affected.听 A landmark European study published just last month found a link between invisible particles of soot and the risk of heart attack.

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Frank Kelly is Professor of Environmental Health at King鈥檚 College London.

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Kelly

It builds on a very large literature which indicates that there is an association between living in an area which has got higher air pollution and a major health outcome, which is heart attacks.听 So the study was done across five European countries, it ran for 12 years and it involved over 100,000 people.

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Porter

And that increased risk was how much?

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Kelly

That increased risk was relatively small, it was the order of between 5 and 10% but it鈥檚 still a听 risk and鈥�

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Porter

Heart attacks are common as well.

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Kelly

鈥� there鈥檚 45,000 people die from heart attacks in the UK every year and if we can help that component of that sector by minimising the risk then I think everybody would be very grateful.

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Porter

So a small increase but in a common thing?

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Kelly

Yes, we all have to breathe.

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Porter

Looking at the pollutants themselves, I mean with the advent of the catalytic converter of course petrol engines were cleaned up and you can鈥檛 smell the fumes like you used to be able to but there鈥檚 a new danger emerged?

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Kelly

Yes, Europeans have got a great love for the diesel engine because we thought it was a more efficient than the petrol engine, we could get more miles to the gallon.听 That鈥檚 not really true anymore and we鈥檙e left really with the problem of diesel being much more of a polluting fuel than petrol is.听 A typical figure that鈥檚 usually used is that you鈥檒l get 20 times more particles from a diesel exhaust engine than you will from a petrol engine.

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Porter

And explain what these particles are.

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Kelly

So these are small carbon particles, so small you can鈥檛 see them.听 And to try and put that into context 鈥� a human hair, which you can just see, is 60 micrometres in diameter, the largest of these particles that can get into your lung are only 10 but the majority of them are much, much smaller than that.听 So they鈥檙e invisible to the naked eye but they鈥檙e produced in very large quantities from all our transport systems and in urban environments.

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Porter

Are modern cars with all of the latest emissions are they still producing these particles?

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Kelly

Modern cars 鈥� they have become cleaner but they haven鈥檛 become clean enough.听 And what has unfortunately has become apparent, just in the last 12 months is, is that these fantastic exhaust systems work beautifully in the factory whenever the car is running to a very set cycle but the technology, it turns out, doesn鈥檛 work that well in real life.听 So if you have a vehicle on a London road, which is running at maybe 12 or 13 miles an hour because of congestion, it never gets up to the right temperature to effectively work properly.听 So we鈥檙e getting a lot more pollution from a vehicle which is meant to be very clean.

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Porter

And how are these particles actually harming us?

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Kelly

The difference about these modern vehicle exhaust particles are that they鈥檙e very small, so they鈥檙e actually getting to parts of our bodies, deep parts of our lung, which particles have never been able to get to before because we鈥檝e always had the larger ones associated with burning wood and coal.听 But these modern diesel associated particles are so small that some of them can actually get across our lung into our circulation.听 Now that鈥檚 never happened to the human lung before but if you get this happening day in, month in, year in over decades then clearly it can build up to a big problem.

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Porter

This new study looked at a link between pollution and heart attack, do we think that these small particles getting into the bloodstream are affecting the heart that way, is that how鈥�?

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Kelly

There are two main theories.听 One is that yes they are transferring across from the lung into the circulation and affecting blood vessels and the heart directly.听 The other theory is that it鈥檚 not the particles themselves but it鈥檚 what they carry on their surface, so they carry these complex chemicals of metals and organic compounds which you get from combustion and then when they get into the deep lung they leach off and they move across the cells into the circulation 鈥� that鈥檚 the chemicals.听 And it doesn鈥檛 really matter, the bottom line is that they鈥檙e getting across whether they鈥檙e on the particle鈥檚 surface or not.

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Porter

What happens to these particles once they come out the back of an exhaust pipe, are they dispersed like gases would be?

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Kelly

Absolutely.听 So immediately beside a busy road there鈥檒l be a high concentration of them and if you happen to be moving along that pavement or whatever you鈥檒l be breathing them in fresh.听 But very quickly they do move up into the air and depending on the weather conditions they鈥檒l be mixed with older particles and they may, if there鈥檚 not high buildings on the road, they may be cleared across out of the city very quickly.

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Porter

What about people who are cycling and pedestrians who are commuting, the children who are walking to school, presumably the more vigorous the activity that you鈥檙e doing in this polluted air the more likely you are to draw these particles in?

听

Kelly

Absolutely, so everything I鈥檝e been talking about so far is to do with concentration of particles in the air.听 Obviously someone who鈥檚 cycling they鈥檙e breathing much harder, or if they鈥檙e running they鈥檙e breathing much harder, if it鈥檚 a child playing they鈥檙e breathing much deeper and longer.听 So it鈥檚 that volume of air and the concentration of pollution in the air which gives you the ultimate figure which we all need to pay attention to.

听

Porter

What about filtering these particles out?听 First of all let鈥檚 talk about the cyclist then 鈥� we see lots of cyclists in London wearing masks, do any masks work?

听

Kelly

Certainly the relatively cheap disposable masks they will not prevent the particles entering the lung because they are too small.听 So effectively if you鈥檙e going to stop those you would have to have something which basically stopped you being able to breathe.听 There are some higher end masks which have activated charcoal as part of their makeup and they will trap some of the gases which we worry about 鈥� we haven鈥檛 talked about those, like nitrogen dioxide which also has health effects 鈥� though actually to stop these very small particles you have a big challenge on your hands.

听

Porter

If it鈥檚 not practical to wear that sort of mask what would your advice to cyclists be?

听

Kelly

So unfortunately many of the major cycle routes are along our busiest roads and that鈥檚 where the most pollution is.听 So there are now apps and maps available which will allow cyclists to plot their route from A to B by maybe adding two or three minutes to their journey but just going down some side roads, some back roads, through parks and they鈥檒l have a much pleasanter experience and they can drop their exposure level to this pollution considerably, I mean many fold.

听

Porter

And to put diesel cars in context, I mean we haven鈥檛 talked about buses and other 鈥� the heavy goods vehicles, but look at the cars 鈥� a modern diesel car compared to the equivalent modern petrol car, how clean is petrol now?

听

Kelly

Very, very clean, the technology for the petrol car has really led to a much improved combustion of the fuel and as a result some of the new Euro Six petrol engines are producing very, very small amounts of particles and very, very small amounts of oxides and nitrogen in the gas.听 If you want to drop pollution with the technology that鈥檚 available at the moment then a small engine petrol vehicle is ideal.

听

Porter

Professor Frank Kelly. And don鈥檛 think you are protected because you are sitting in a car - most modern automotive filters are not fine enough to remove diesel particulates, and you are breathing the same air as the cyclists and pedestrians.

听

Just time to tell you about next week when I will be looking at the latest thinking on how to manage children with constipation. And another cause of cough, but this one makes your chest sound like it鈥檚 full of Velcro.

听

ENDS