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Blood pressure pills and cancer, Aortic aneurysm repair, Sinks and hospital infection

The programme gets some clarity behind recent headlines that link cancer to pills for high blood pressure. Plus, how sinks could be causing hospital infections.

Clarity behind recent headlines linking cancer to pills for high blood pressure; Margaret McCartney unpicks the numbers. And the aorta is the largest artery in the body so should it burst due to an abdominal aortic aneurysm, results can be catastrophic. Now Surgeons are concerned that restricting the use of the latest keyhole techniques to repair aneurysms would be a backward step and harm patients. Plus how sinks could be causing hospital infections.

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ProgrammeTranscript - Inside Health

Downloaded from www.bbc.co.uk/radio4

 

THE ATTACHED TRANSCRIPT WAS TYPED FROM A RECORDING AND NOT COPIED FROM AN ORIGINAL SCRIPT.  BECAUSE OF THE RISK OF MISHEARING AND THE DIFFICULTY IN SOME CASES OF IDENTIFYING INDIVIDUAL SPEAKERS, THE BBC CANNOT VOUCH FOR ITS COMPLETE ACCURACY.

 

 

INSIDE HEALTH – Programme 6.

 

TX:  30.10.18  2100–2130

 

PRESENTER:  MARK PORTER

 

PRODUCER:  ERIKA WRIGHT

 

 

Porter

Hello.  Coming up in the next half hour:  Problems with the pipes, how plumbing could be causing infections in hospital.  Suffice to say, you’ll never look at a sink in quite the same way again.

 

Clip

Basically, all the sewage systems are connecting every single sink.  So, this piping – every single room in a certain ward but sometimes even in an entire department – is interconnected.  So, this is the ideal route, basically, through which a multi-drug resistant bacteria can move from one room to another and cause a major outbreak.

 

Porter

Yuk.  And new guidance from NICE on treating aortic aneurysms.  Surgeons are concerned that restricting the use of the latest keyhole techniques would be a backward step that will harm patients.

 

Clip

I think if we look at the international models and international guidelines we’re going to be very isolated.  So, there is general shock amongst aortic surgeons internationally at the fact we may be going back 20 years in our practice.

 

Porter

But first, new research linking cancer to a widely used pill for high blood pressure.  Here’s how the Today programme mentioned it:

 

The Today programme clip

The Times and Telegraph report on a new study which suggests millions of people are taking blood pressure drugs which have been linked to an increased risk of developing lung cancer.  The Telegraph says almost a million Britons were involved in the study which found people who had taken ACE inhibitors for 10 years or more were up to 31% more likely to develop the disease.

 

Porter

Alarming, if you happen to be one of the many in the UK taking an ACE inhibitor, that’s drugs ending in pril – like ramipril and perindopril. The new research suggests that you have to be on the pills for at least five years, and the longer you take them the greater the association with cancer.  And ACE inhibitors are not just prescribed for high blood pressure, but for heart and kidney problems too.

 

Dr Margaret McCartney is in our Glasgow studio.  Margaret, what was your initial reaction?

 

McCartney

Absolute fury and then incandescence, I’m afraid Mark.  This is a primary example of relative risks being used to try and explain what’s happened in a study and it’s just not good enough.  A 30% increased risk – well you have to know what was your risk to start with because if you don’t know that you can’t work out how big this extra risk could be.

 

Porter

So, what you’re saying, Margaret, is worrying though 30% is, if it’s 30% of not very much, it’s not very much.

 

McCartney

Exactly.  And this is not very much.  So, let’s look at the numbers.  Patients using ACE inhibitors over the average of 6.4 years of the study, .95% of them were noted to have lung cancer by the end of it.  This is compared to the patients using ARBs, the similar but not quite the same drugs, there was .91% of those patients developed lung cancer over the duration of the study.  That is a difference of 0.04% - that is tiny.  That means that 2,500 patients had to be prescribed these ACE inhibitor drugs over the duration of the studies for one extra case of lung cancer to be picked up.  For an individual patient that risk is very small indeed.

 

Porter

So, the 30% figure comes from where?

 

McCartney

So, they actually used 31% in the press release, just from rounding up.  But this is the relative risk.  So, this is the small amount of increase within that absolute risk of percentage.  But the problem is, that it’s not clear, I think, for people listening to that, what the level of risk is for them.  Now there are other problems with this study.  For example, there had to be a lot of adjustments done because obviously smoking increases the risk of lung cancer per se, so you have to make sure your groups are equal from that point of view.  This is not the kind of study that we can rely on completely to show us that using these type of drugs increases the risk of lung cancer.  It’s an interesting study but this is not something that’s unduly worrying me because I don’t see it as being a definite risk and I don’t see it as something that has been proven.  And looking at it in perspective – if a million people were on these ACE inhibitors and using them for prolonged periods of time and this association is true, you might be expected to see 400 more cases of lung cancer over that timeframe but that’s really a drop in the ocean about how many lung cancers are caused overall and of course if we want to reduce lung cancer then the prime way to do that is increasing smoking cessation rates.

 

Porter

If there is, indeed, a link, however small, do we have any idea why there’s a link?

 

McCartney

Well there is and there’s all kinds of theoretical reasons as to why this might be.  ACE inhibitors produce a substance called bradykinin, that the ARB class of drugs don’t seem to, there is a theoretical reason why that might increase the risk of lung cancer.  Having said that though, Mark, a few years ago people were worried that calcium-channel antagonists, another group of drugs used for blood pressure, there was a concern that perhaps they might increase lung cancer risk.  But later on, randomised control trials have really disproved that.  So, I think it’s fine to bring up theoretical reasons as to why you should be concerned about something and definitely good to look into it but I think the problem occurs when press releases go out that put relative risks in rather than absolute risks and our read out on the Today programme and alarm rather a lot of people.

 

Porter

If we’ve said it once, we’ve said it numerous times but half of bugger all is still bugger all.

 

Thank you very much, Margaret.  More details, as ever, on the Inside Health page of the Radio 4 website.

 

The aorta is the largest artery in the body.  At around two centimetres in diameter, it’s the size of a garden hose pipe, but under much higher pressure – enough to send a column of blood nearly two metres into the air.  Just imagine the consequences if it were to leak or burst. 

 

Well that is exactly what can happen with an abdominal aortic aneurysm – where the artery balloons due to weakening of its walls as it travels down behind the stomach and bowel. 

Burst aneurysms kill 3,000 people every year in the UK, which is why we now have a national screening programme designed to catch the swellings at an earlier stage so they can be electively repaired before they rupture.  Every man is now invited for an ultrasound scan of their abdomen when they reach 65 – it is not offered to women as they are at lower risk.

 

Around 300,000 men are screened every year and in 2014/15 it picked up 2,773 aneurysms in England alone, nearly 700 of which were subsequently operated on.

 

Peter Laker’s aneurysm was caught early – albeit, not through screening, but during investigation for another problem.

 

Laker

I was in hospital for another reason, I had a CT scan and the fact that I had an aneurysm was picked up then.

 

Porter

And at the time you had no idea that you had a problem?

 

Laker

I didn’t even know what an aortic aneurysm was at that time.  I had six monthly scans after that to see what size.  Didn’t really worry me.  The main concern was when a very, very good friend, who’d holidayed in the South of France, wouldn’t let his partner take him into hospital in France, driving back, it burst, nothing they could for him.  And I think that is when it started to hit home for me.

 

Porter

Because it must feel a little bit like you’ve got a ticking timebomb, to some extent, particularly when that happens to a friend of yours.

 

Laker

Yes, it was, yes, yes, yes.  Earlier this year I was referred to St George’s for surgery.

 

Porter

What was it like when you woke up after the operation – how did you feel?

 

Laker

Pretty grim actually, but I was in intensive care following the op.  Less than 24 hours I was up – I was on my feet.  Felt absolutely wonderful and I was thrown out the following day I think.

 

Porter

Peter was in and out of hospital so quickly because he had an endovascular repair.  A keyhole technique to insert a new lining, or stent, into the weakened portion of his aorta, as opposed to the more conventional open operation to replace the diseased section with a synthetic tube.

 

But new guidance from NICE, due to be published at the end of the year, looks set to severely restrict the use of this new keyhole technique, a move that worries many surgeons.

 

Professor Ian Loftus operates at St George’s University Hospital NHS Foundation Trust in London, but spoke to Inside Health in his role as President Elect of the Vascular Society.

 

Loftus

We have two options – the first, being open surgery.  That involves making a large cut and replacing the aneurysm with a by-pass graft essentially.  That’s a big operation, usually takes three hours and involves a stay in intensive care.  And on average in the UK a stay in hospital of around eight to 10 days.  Importantly the recovery period is quite prolonged, so it takes people three to six months to get back to full activity.  We know that surgery also comes with quite a lot of risk, risk of not surviving of three in a hundred at the moment in the UK but also risk of serious complications – around 10 in a hundred.  The alternative is the keyhole surgery, that we use, and that is much safer, it’s much less invasive, so the risks are 10-fold less than for open surgery.  But also, the recovery is much quicker.  So, we know patients can be treated, on some occasions now, as a day case but on average with two to three days stay in hospital.  They often don’t need a stay in intensive care, are walking straightaway and can get back to normal activities, often within a week or two.

 

Porter

Well anyone listening to that, if suitable, is going to want to go for a minimally invasive option, I mean it sounds a bit of a no brainer to me, so where’s the catch?

 

Loftus

The catch is long term.  So, with a stent, although the recovery is much quicker and the risks are much lower, it does involve a lifetime in surveillance – or when I say surveillance that means having scans once a year to ensure that there are no problems with the stents.  There are occasions when stents require relining or further procedures are required.  And that does add to the cost in the lifetime of the patient, in terms of reintervention.

 

Porter

And is that what’s behind the NICE decision that this, although better for the patient possibly, is more expensive and the NHS can’t afford it?

 

Loftus

Very much so.  And there’s no doubt that the major trials, particularly the major trial of the keyhole technique in the UK, does show that in the long term it is more expensive.  But that said, certainly in the UK we used to have quite high rates of death from aneurysm surgery, electively, and that’s been addressed from a number of reasons but the main reason we’ve made quite a dramatic reduction in the risk from surgery is the use of keyhole techniques.

 

Porter

But why is there such a big difference in cost of follow up from the two different procedures?  What happens when you have an open operation?

 

Loftus

With an open operation often there’s just a single outpatient appointment with the consultant who performed the surgery and if all is seen to be well the patient is discharged back to the care of their general practitioner.

 

Porter

So, effectively, they’re not actually followed up really?

 

Loftus

No that’s right.

 

Porter

Long term.

 

Loftus

There’s very little follow up in the long term.  And if the NICE guidance came into clinical practice there are two consequences to that.  One is, having to do more of the open surgery and that will, without doubt, lead to higher death rates from the surgery.  But the second consequence is there will be a large proportion of patients who will be deemed unfit for surgery.  And that is bound, therefore, to increase the risk of rupture.

 

Porter

What happens if you don’t catch the aneurysm as it’s growing but it bursts?

 

Loftus

So, the concern is when it bursts, firstly getting to a hospital that can fix it quickly, only around one out of four will make it to hospital.  Then if you make it to hospital you’ve still only got around a one in two chance of surviving.  So, ruptured aneurysm is a very bad condition, it’s a catastrophic condition from which only around one in five will survive.

 

Porter

But the pending NICE decision is based on the best evidence out there.

 

Loftus

Largely NICE have focused very much on the trial data, which of course is our gold standard in guiding clinical practice but I think it’s unfortunate that’s been taken largely in isolation.  We do know now, looking at those trial data, that practice has evolved.  In the UK we have a national vascular registry which the public can access.  There are limitations with registry data but when registry are combined with other data sets it can be very powerful and I do feel strongly that we should be using those contemporary data to base our current practice.

 

Porter

But why haven’t we got contemporary randomised control trial data?  What you’re suggesting is that the trail data they’re looking at is out of date?

 

Loftus

Well the trials were performed a long time ago, so the UK trials were now 15-20 years ago and because they showed early benefit of endovascular surgery, significant early benefit in terms of death, we all saw that as the gold standard at the time based on those trials.  I don’t think any of us particularly expected the long-term outcomes to be used in a way that would potentially prevent us using the technology and so the trials haven’t been repeated.

 

Porter

Looking at a case like Peter’s, he’s made an excellent recovery, if Peter was to come and see you next year with the problem that he had this year you won’t be able to offer him the operation, would you operate on him at all?

 

Loftus

It’ll be a very difficult consultation because I will know what I could do but what potentially I won’t be able to do.  And my major concerns – because I think in Peter’s case I wouldn’t be prepared to offer him open surgery, I think it would be too high risk for him, so I would have to explain that to him.  And there are two major problems with this for me – one is the anxiety that causes him, his friend died of a ruptured aneurysm.  There’s also the aspect of independence, so when you have an aneurysm that’s of a size that we as a surgeon feels should be repaired, he’s not allowed to drive, he won’t get insurance, he can’t travel.  I’m not sure how we deal with that, I’m not sure how we’re going to counsel patients because we simply won’t be able to offer them the treatment we know we can.

 

Porter

And to be clear:  The reason that you wouldn’t perhaps offer him an operation is that he’d be too much of a medical risk because he has other health issues and you’d be concerned that the surgery would do more harm than good?

 

Loftus

Yes, so someone like Peter, there’s an element of guesswork in guiding him as to what the risk of open surgery would be but I’ve looked at his physiology and I suspect he’s probably around a one in 10 risk from the open surgery, probably higher.  That’s a very high risk…

 

Porter

Of not surviving the operation.

 

Loftus

Of not surviving the operation.  Plus at least a one in 10 risk of a serious complication.  But we know that from our contemporary data that actually the risk of the keyhole surgery is 10-fold less.  Not just of death but of serious complication – whether it’s heart, lung, kidney.  So, it is a far less invasive procedure.

 

Porter

What about the chances of an aneurysm like that rupturing and the same happening to Peter that happened to his friend, had he not had surgery?  Can you predict that?

 

Loftus

Very difficult to predict but the historical data would suggest once it reaches six centimetres, which was Peter’s level, his risk of rupturing in the next year is at least one in 10.  Once you reach seven centimetres, and in Peter’s case it was growing reasonably fast, it’s one in three.  So, the risk gets higher and higher as the aneurysm expands.

 

Porter

What have you done about this, as the President elect?  You’re obviously concerned about it.

 

Loftus

We, and many others, across the country have raised concerns with NICE.

 

Porter

But the NHS is short of money.

 

Loftus

And I absolutely understand that, we are in a cash limited environment in our healthcare system and there did need to be discussion about rationing or rationalisation of the technology that is required.  There are some of the very older frail patients who perhaps we shouldn’t operate on.

 

Porter

Because the flip side, and one of the criticisms of keyhole surgery has been, that because it’s less invasive surgeons are offering it to people that they otherwise wouldn’t want to operate on – people who are very frail – and that actually the evidence suggests it doesn’t do them a lot of good in terms of survival.

 

Loftus

Yes, most vascular surgeons in the UK would share that view and I think that’s across the board in surgery actually, as technologies evolve we learn where we should and where we shouldn’t use it and I think that’s one of the areas in aneurysm surgery that we have learnt that they are patients who we can treat who perhaps we shouldn’t.  But I think if we look at the international models and international guidelines we’re going to be very isolated.  So, there are American guidelines and new European guidelines which are just about to be published which are in conflict with what NICE currently through their draft guideline are recommending.

 

Porter

And that conflict comes about – is about the cost then because they must be looking at the same evidence?

 

Loftus

Partly cost but also looking more broadly at evidence.  So, the recent European guidelines which have involved an international group of very experienced aortic surgeons have looked at the full body of evidence, not just randomised control trials but more contemporary data and have guided surgeons towards open surgery in young fit people and conservative measures in unfit people.  But the middle group, which are actually difficult to predict, have recommended the keyhole surgery.  So, there is general shock amongst aortic surgeons internationally at the fact we may be going back 20 years in our practice.

 

Porter

Do you know of any other field in surgery where advances, the less invasive, the keyhole forms, are not being used and we’re reverting back to the older techniques?

 

Loftus

No, none whatsoever, and I think that’s where I’m particularly shocked at this proposed guideline because across the board we’re seeing dramatic developments in surgical techniques.  So, there is a precedent being set here, if we start thinking about – purely about the cost of our surgical interventions there is a danger that this will spread across other more expensive surgical techniques.

 

Porter

Will you personally end up operating on fewer people do you think?

 

Loftus

Yes, without doubt.

 

Porter

Professor Ian Loftus. Well, we asked NICE for a comment, and were sent this by Paul Chrisp, director of the Centre for Guidelines at NICE:

 

NICE comment (read)

The draft guideline aimed to clarify when unruptured and ruptured aneurysms should be repaired and what surgical method – open or minimally invasive endovascular repair – is most appropriate, cost effective and best for patient care.  This was the subject of public consultation, and feedback received during that process, including from the Vascular Society, is currently being carefully considered ahead of publication of the final guideline.

 

 And there is a link to a draft of the proposed NICE guidance on our website.  With the final version due in December.

 

Plumping noises

 

Time now for some more conventional plumbing challenges.  [Plumping noises] And new research identifying hospital sinks as a source of infection – in this case with gram negative bacteria, a group responsible for around a third of all hospital acquired infections, including pneumonia, a particular problem on intensive care units.

 

Consultant microbiologist Joost Hopman is Head of Infection Control at Radboud University and Pantein Hospitals in the Netherlands.

 

Hopman

Well sinks are a source for multi-drug resistant bacteria because they are in very close proximity to our patients and many materials – urine or some sputum or other biological waste, medication etc. – go down the drain in those sinks.  And thus, they are source for bacteria and for outbreaks.

 

Porter

And the bacteria are living deep in the drainage system of the sink or do they live on the sink surface itself?

 

Hopman

They are living on surfaces as well, however, if you do cleaning and disinfecting practices within a hospital you would remove those superficial biofilms within the sink.  The real problem, however, is underneath the sink, is in the P trap, where obviously you cannot clean and disinfect and in this P trap you will have the ideal environment for bacteria to become really multi-drug resistant.

 

Porter

Do we understand how infection might be from a sink to a patient, given that you would hope the water’s going one way and that’s down?

 

Hopman

Basically, all the sewage systems are connecting every single sink in the different patient rooms, even if you have single patient rooms, as we have nowadays, in most of our Dutch hospitals.  So, despite being every single room in a certain ward but sometimes even in an entire department is interconnected, so this is the ideal route basically through which a multi-drug resistant bacteria can move from one room to another and cause a major outbreak.

 

Porter

Is there something about the environment in the sink that makes it more likely to host bacteria that are resistant to some of the antibiotics that we use, troublesome bacteria?

 

Hopman

Well actually there is, so there is a very interesting new publication out just from the US where they did an investigation using cameras in very close proximity to the sinks where they recorded all activities related to these sinks.  So, a fascinating story and the study shows basically that sinks are only used in 4% of the cases for handwashing and for all the other activities – medication preparation and discarding of detergents and disinfectants and biological waste – the sinks are used for these activities more often.

 

Porter

Tell me about your research in the intensive care unit.

 

Hopman

So, what happens already now in 2014 is that we encountered an outbreak in our intensive care unit with a multi-drug resistant bacteria and we were able, because of microbiological investigation, to relate this outbreak back to the sinks.  In that moment of time little was known about interventions that you could do to stop and halt such an outbreak.  So, what we did is a systematic review and what we found is actually that there were already first publications about the relationship between sinks and infections a long time ago.  So, it was already in the 1970s in England where a physician identified these sinks as a possible source for bacterial infections in Somerfield Hospital in Birmingham.  So, this was already 40 years ago in a burns unit and in a burns unit the patients are extremely vulnerable from multi-drug resistant bacteria because their skin and their first barrier to bacterial infections is gone.  So, nowadays we are in the midst of a huge renovation and there will be newly built part of the hospital and in-patient rooms sinks will not be constructed.

 

Porter

Joost Hopman.  And Margaret McCartney’s been listening to that.  Margaret, it seems that much of that new hospital won’t actually have anywhere for staff to wash their hands, which is counterintuitive.

 

McCartney

It sounds almost outrageous doesn’t it, no running water around, we always think about sinks and handwashing as something that’s so crucial.  But in fact, I think it’s really healthy to start thinking – is something that we know has caused many advantages actually also causing unintended side effects.  And I think part of the problem is when you wash your hands with soap and water and you are cleansing the water that is dripping from your hands back into the sink you can get a very fine mist, a very fine aerosol, created from your dirty water that you’re trying to rinse away and that can spread and spread infection as it does so.  So, an unintended hazard of something that we know is essentially a good thing.

 

Porter

And that’s the same mechanism for bugs that are existing in the P trap and the drains and coming up to underneath the plug hole, when you turn the tap on full blast you’re getting those same aerosols forming presumably.

 

McCartney

That’s presumed to the case.  In my local hospital, the Queen Elizabeth Hospital in Glasgow, there have been reported problems over the last few months with drainage systems, children getting infected in some wards, and the theory is that there’s a problem within the sink, the drainage systems, within the hospital.  They’re put on new filters onto the taps, they’ve done special cleaning with drains and the feeling is that there’s a biofilm, sort of almost like scum, building up within the system that’s very difficult to get rid of and clean, even with the very best of intentions.

 

Porter

Joost mentioned there, Margaret, obviously his own research and the study here in the UK, that was done some 40 odd years ago, what about the rest of the world, what’s been happening in between?

 

McCartney

Yeah, I mean there’s certainly been studies in Spain, additionally, finding very similar things, that you can reduce the amount of gram negative bacteria carried by patients when you have these sink free systems.  And it sounds almost unthinkable.  And I have a bit of a confession to make.  So, I’m quite interested in medical history and I remember reading the story of Ignaz Semmelweis, who was a Viennese physician in the 1800s and he’s meant to be the father of handwashing and I’d always thought that he invented soap and water.  And the story is that he noted that the death rate of mothers in one ward was much higher than the other and he ascribed this to the fact that the high death rate was because medical students and doctors returned from doing autopsies, went straight to do examinations on pregnant and labouring women, and he ascribed the fact that the larger death rate was to do with something that these medical students and doctors carried on their hands along with them.  And when he introduced his interventions the death rate fell.  And I had always thought that was handwashing itself, in fact it wasn’t, he actually introduced the use of chlorinated lime, a kind of antiseptic solution even then.  So, I just find it really interesting that even then it wasn’t just water and handwashing that seemed to save lives, it was actually using other antiseptic solutions as well.

 

Porter

That was the 19th century version of the sort of Alco rubs that we use now.

 

McCartney

It seems to have been and it certainly did make a huge difference and the mortality rate fell dramatically after that and in Vienna I think he’s really adored as someone who really put medicine forward.

 

Porter

Thank you, Margaret.

 

Well that’s it for this series of Inside Health.  Sorry if you were expecting to hear our report on pre-eclampsia that I trailed last week.  It will be in the next series, which starts just after the New Year.

 

Please get in touch in the meantime with ideas for subjects you think we should investigate. Contact details are on the Inside Health page of the Radio 4 website, where you can also subscribe to our weekly podcast and spend the next couple of months catching up on episodes that you’ve missed.

 

So, until January, goodbye.

 

ENDS

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