Monthly Archives: March 2017

Cholesterol lowering – proven or not?

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Repatha

Just before I head off on holiday for a couple of weeks, I thought I should make a quick comment on the Repatha trial (PCSK9- inhibitor). I have written much about this new class of cholesterol lowering drugs, and I have been highly skeptical that they would have any benefits on cardiovascular disease. [Mainly on the basis that I don’t believe raised LDL causes CVD, and these drugs have one action – to lower LDL].

As many of you will be aware, the data from a clinical trial on Repatha has just been released. It was reported by the BBC thus

‘Huge advance’ in fighting world’s biggest killer.’

An innovative new drug can prevent heart attacks and strokes by cutting bad cholesterol to unprecedented levels, say doctors. The results of the large international trial on 27,000 patients means the drug could soon be used by millions.

The British Heart Foundation said the findings were a significant advance in fighting the biggest killer in the world. Around 15 million people die each year from heart attacks or stroke. Bad cholesterol is the villain in the heart world – it leads to blood vessels furring up, becoming easy to block which fatally starves the heart or brain of oxygen.

It is why millions of people take drugs called statins to reduce the amount of bad cholesterol . The new drug – evolocumab – changes the way the liver works to also cut bad cholesterol. “It is much more effective than statins,” said Prof Peter Sever, from Imperial College London.

He organised the bit of the trial taking place in the UK with funding from the drug company Amgen. Prof Sever told the BBC News website: “The end result was cholesterol levels came down and down and down and we’ve seen cholesterol levels lower than we have ever seen before in the practice of medicine.”

And so on, and so forth. So, the Repatha trial was a huge success. Obviously, it certainly lowered LDL to levels never seen before. Or, maybe it was not quite such a huge success. Michel de Logeril, a professor of cardiology in France – who set up and ran the famous, and successful, Lyon Heart Study sent me this comment.

‘This is just junk science.

The calculated follow-up duration required to test the primary hypothesis was 4 years as written by the authors themselves (but only in the second last paragraph before the end of discussion…) but the actual median duration of follow-up has been 2.2 years; it is thus a biased trial (a similar bias as in JUPITER: 1.9 years instead of 4 years): early stop!

In addition, contrary to the misleading claims in the medias, there was no effect on both total [444 deaths with evolocumab vs. 426 with placebo] and cardiovascular [251 vs. 240] mortality; which is not unexpected with a so short a follow-up.

They pretend that they are differences for non-fatal AMI and stroke but there is no difference in AMI and stroke mortality… Very strange… It would be critical to get access to the raw clinical data to verify the clinical history of each case in both groups.

Well, in my opinion and given the present state of consciousness among US doctors, FOURIER is a flop!

Best

Michel’

What he is saying, is that there was a reported reduction in non-fatal heart attacks and stroke. And less need for revascularization procedures e.g. PCI/stents. As you may gather Professor de Logeril would like to see the raw data to verify this. There is very little chance that this will be made available.

Anyway, that was the upside.

The downside is when you look at cardiovascular deaths.

  • The total number of deaths from cardiovascular disease in the Repatha group was 251
  • The total number of deaths from cardiovascular disease in the placebo group was 240
  • So, 11 more people died of cardiovascular disease in the Repatha group

The overall mortality data

  • The total number of, overall, deaths in the Repatha group was 444
  • The total number of, overall, deaths in the placebo group was 426
  • So, there were 18 more deaths in those taking Repatha.

The differences here are not large enough to be statistically significant. However, there were more, not less, deaths in the Repatha group, and more, not less, CV deaths. This study was also terminated early, which is extremely bad news for any clinical trial, and casts enormous doubt on any findings. It was supposed to last four years, but was stopped at 2.2 years. Why? Were the mortality curves heading rapidly in the wrong direction.

Alongside this, should be set the knowledge the Pfizer also had a PCSK9-inhibitor undergoing clinical trials, and they pulled the plug, right in the middle of it all.

Pfizer Ends Development Of Its PCSK9 Inhibitor

‘November 1, 2016 by Larry Husten

Immune issues and diminishing efficacy doomed the new drug.

Pfizer announced on Tuesday that it was discontinuing development of bococizumab, its cholesterol-lowering PCSK9 inhibitor under development.

“The totality of clinical information now available for bococizumab, taken together with the evolving treatment and market landscape for lipid-lowering agents, indicates that bococizumab is not likely to provide value to patients, physicians, or shareholders,” the company explained.

Pfizer said that it would halt two very large ongoing cardiovascular outcome studies with bococizumab, the 17,000 patient SPIRE 1 trial and the 10,000 patient SPIRE 2 trial. The trials were fully enrolled.’

Pulling the plug when 27,000 patients had been fully enrolled. What on earth did they see. Something more than slightly worrying. I guess we will never really know, but that is one hell of a write off.

It is also interesting to note that Amgen – the company selling Repatha, has announced that:

‘Amgen to refund cholesterol drug if patients suffer heart attack

Pledge aims to convince insurers to pay for $14,000-a-year medicine.’ 2

As reported in the Financial Times.

This is a big vote of confidence … not! I think, perhaps, we are looking at a doomed drug. Probably a doomed class of drugs. Has the cholesterol hypothesis been verified, or contradicted? I know I am biased, but I know what I think.

1: http://cardiobrief.org/2016/11/01/pfizers-ends-development-of-its-pcsk9-inhibitor/

2: https://www.ft.com/content/34154cdc-0a86-11e7-ac5a-903b21361b43

What causes heart disease part XXVIII

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Viagra

For those who have read my endless series of blogs on cardiovascular disease, you may know exactly where I am going at this point.

Some time ago, Pfizer were developing a drug to treat angina. It blocked an enzyme called phosphodiesterase type-5. [Although I believe that its exact mechanism of action was not known at first]. To put it another way, this drug was a phosphodiesterase type-5 inhibitor (PDE5i).

The moment Pfizer found out what enzyme this drug blocked, they tried to patent the pathway that blocked this enzyme. Pharmaceutical companies trying to patent biological pathways. Perhaps I should try to patent the Krebs cycle, and charge everyone on the planet for having such a thing. Kerchingggg!

‘The U.S. patent office appears to have granted Pfizer a patent covering any drug that blocks this enzyme, meaning that it can sue all of its potential competitors.’1

Luckily, this time they were rebuffed.

Anyhoo, back to the drug. During phase one clinical trials, where humans are given the drug for the first time to see what effects it may have, many of the volunteers were hanging on to their medication, rather than handing them back. This was very unusual. Almost unknown in fact.

When researchers went out to find out why this was happening it was discovered, not quite sure who admitted to this, that sildenafil/Viagra improved erectile function. Thus, Viagra, the first PDE5i, was born. The first drug that worked simply and effectively to improve erectile dysfunction (ED). As for treating angina… that piffling indication was rapidly shelved as the dollar signs appeared in the sky above Pfizer HQ. Sex, as they say, sells.

In truth, it is actually one of the best drugs ever. Not only does is treat ED, but it can also be used by mountaineers to prevent pulmonary oedema (fluid filling up in the lungs), which is one of the major symptoms of altitude sickness. It does this by reducing the blood pressure in the pulmonary vessels (blood vessels in the lungs).

To explain a little further. If you climb very high, and the oxygen level drops, the heart pumps blood harder and harder through the lungs to get as much oxygen as possible into the system. This can result in fluid leaking out of the vessels and into the lung tissue, so they fill up with fluid. At which point you effectively drown, so you die. Viagra stops this happening, by lowering the blood pressure in the lungs.

Unsurprisingly, Viagra is used to treat people who have pulmonary hypertension (high blood pressure in the blood vessels in the lungs) at sea level. It is sold under the name Ravatio, for this indication – but we know that it is just Viagra. In addition, Viagra can be used to treat Raynaud’s disease, where the small blood vessels supplying the fingers and toes constrict, leading to painful cold fingers.

So, here we have a drug that can treat angina, pulmonary hypertension, erectile dysfunction and Raynaud’s disease at the same time. Thus, you can have great sex at twenty thousand feet above sea level, not get chest pain, or breathless, and stay warm at the same time. What more could a man ask for?

How does it do all these things? The answer is that it increases Nitric Oxide (NO) synthesis in endothelial cells. When it does this in the penis, it stimulates erections. In the heart, it opens up coronary arteries. In the lungs, it dilates the blood vessels, in fingers and toes it opens up arteries. So, all of the many different effects, are all due to exactly the same process – increased NO synthesis. Viagra also lowers blood pressure – as you would expect.

At the risk of blowing my own trumpet, I talked about this in my book ‘Doctoring Data,’ under the heading ‘Viagra and the drugs of unintended consequences.’ I posed the question. ‘If we were to prescribe Viagra as an antihypertensive, which is entirely possible, and it were found to reduce the risk of heart disease and stroke, which effect do you think would be responsible for the benefit? The blood pressure lowering effect, or the anticoagulant effects? Or something else.’

Since I wrote those words, someone has actually looked at the impact of PDE5is on cardiovascular disease. Researchers at Manchester University, in the UK, studied the use of Viagra in people with diabetes – who often have erectile dysfunction. Here is what they found:

‘Viagra could prevent heart attacks, according to research. Patients taking the male impotence drug were found to have a lower risk of having a heart attack or dying from heart failure than those not on the medication. The lead scientist told the Daily Express the findings are “incredibly exciting”.2

The research paper was published in ‘Heart’, a BMJ journal. Actually, this paper was published last year, but only seems to have hit the press in the last few days. I spotted it in the Times a few days ago.

Here are the main results (for those readers who like their statistics)

‘Results: Compared with non-users, men who are prescribed PDE5is (Viagra, Cialis and the like – my words) (n=1359) experienced lower percentage of deaths during follow-up (19.1% vs 23.8%) and lower risk of all-cause mortality (unadjusted HR=0.69 (95% CI: 0.64 to 0.79); p<0.001)). The reduction in risk of mortality (HR=0.54 (0.36 to 0.80); p=0.002) remained after adjusting for age, estimated glomerular filtration rate, smoking status, prior cerebrovascular accident (CVA) hypertension, prior myocardial infarction (MI), systolic blood pressure, use of statin, metformin, aspirin and β-blocker medication. PDE5i users had lower rates of incident MI (incidence rate ratio (0.62 (0.49 to 0.80), p<0.0001) with lower mortality (25.7% vs 40.1% deaths; age-adjusted HR=0.60 (0.54 to 0.69); p=0.001) compared with non-users within this subgroup.’3

For those who don’t like their statistics quite as much as me (shame on you). I shall attempt to simplify.

  • Over a seven year period, those men taking PDE5is (Viagra Cialis and the like) had a 4.7% reduction in overall mortality – compared to men who did not.
  • Those taking Viagra were 38% less likely to have a myocardial infarction
  • If you did have a myocardial infarction, those who were taking PDE5is had a 25.7% death rate. Those who were not taking PDE5is had a 40.1% death rate. So, if you were unfortunate to have a heart attack, you were 14.6% less likely (absolute risk reduction) to die if you were taking PDE5is.

Or, to shorten this even more

  • 4.7% reduction in overall mortality
  • 38% reduction in MI (relative risk reduction)
  • 14.6% reduction in death after an MI

Whilst the first figure of a 4.7% reduction in overall mortality may not sound terrible exciting, it knocks all antihypertensives and cholesterol lowering medication into a cocked hat. Even if you add them together and multiply by two – on their best day. Because 4.7% is an absolute risk reduction. [Absolute mortality reduction in the Heart Protection Study (HPS), the most positive statin trial, was 1.8% over five years]

The benefits of Viagra are even more startling when it comes to having a heart attack (MI). The current ‘gold standard’ treatment of choice is Primary Percutaneous Coronary Intervention (PCI), which basically means popping a stent into a blocked coronary artery to open it up again.

It has been estimated that PCI results in a 2% absolute reduction in mortality4. On the other hand, Viagra gives you, very nearly, a 15% reduction in overall mortality. Or, to put it another way, Viagra may be seven and a half times as effective as PCI.

But it does not end here. it was also found that men with heart failure were 36% less likely to die if they took a PDE5i.

‘In the other subgroups, there was an inverse association between PDE5i use and all-cause mortality. Those with a recorded history of congestive cardiac failure, TIA and PVD had 36%, 40% and 34% lower risk, respectively.’ [A TIA is a transient Ischaemic attack/small stroke. PVD is peripheral vessel disease.]

Congestive cardiac failure is usually shortened to heart failure. [This 36% is a relative risk reduction, and I could not work out what the absolute risk was from the paper. I am probably too thick].

The effect on heart failure is almost certainly because another benefit of increasing NO is that you increase ‘angiogenesis’, otherwise known as, ‘the creation of new blood vessels’. If a coronary artery does completely block, this often leads to heart failure, as not enough oxygen and other nutrients can get into the heart muscle downstream.

However, if collateral blood vessels develop, the blood will be directed around the blockage and back into the artery downstream, through these newly created blood vessels. Although collateral circulation is not as effective as a fully patent coronary artery, it will create a significant flow of oxygen and nutrients once more. Thus, heart failure will be greatly improved.

Louis Ignarro, who identified nitric oxide (NO) as the key chemical messenger that dilated blood vessels, and won the Nobel Prize for doing so, decided to start treating people who have end stage heart failure with l-arginine. He had been looking for a substance that would, naturally increase NO, and found l-arginine did the job best. He has had some amazing results. Perhaps he should start using Viagra instead.

This study, I must add, was not interventional, it was observational. However, it strongly supports the hypothesis that increasing NO synthesis is just about the most important thing you can do. If you want to avoid dying from CVD.

Do I think everyone should take Viagra? Well, if you have heart failure, diabetes and a high risk of CVD – probably. Will you get a doctor to prescribe it for you, for CVD prevention? Absolutely no chance. Will anyone ever fund a study on this? With the drugs now off patent – no chance.

Oh, the joys of modern medicine. Unless someone does a controlled randomised double blind study on a medication, doctors will not prescribe – are not allowed to prescribe. However, virtually the only people with the money to do such studies are pharmaceutical companies. If the patent life of a drug has expired, no money can be made. So, no trial will be done. So, drugs that are almost certainly beneficial wither on the vine.

Unusually, for me, I do not blame the pharmaceutical companies for this. They are not charities. They need to make money or they die. You cannot expect them to spend hundreds of millions on a clinical study, without any possible means of gaining a return on their investment. We live in a funny old world.

In the meantime, look to other things that can increase NO synthesis. L-arginine/L-citrulline does this. Potassium does this. Sunlight does this. Exercise does this. Meditation does this. Vitamin D does this, as does Vitamin C. What are you waiting for? Go for a walk in the sun and eat an orange – you will live forever.

 

1: https://www.forbes.com/2002/10/23/cx_mh_1023pfizer.html

2: http://www.independent.co.uk/life-style/health-and-families/health-news/viagra-could-lower-heart-attack-risk-and-risk-of-dying-from-heart-failure-a7082801.html

3: http://heart.bmj.com/content/early/2016/07/26/heartjnl-2015-309223.full

4: https://www.ncbi.nlm.nih.gov/pubmed/12517460?access_num=12517460&link_type=MED&dopt=Abstract

What causes heart disease part XXVII

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Lumen: The lumen of the artery is the hole in the middle that the blood flows through.

The artery wall: The artery wall is made up of three layers: Endothelium/intima, media and adventitia

The endothelium: Usually thought of as a single layer of endothelial cells than line the lumen of the artery. [The layer may be more than one cell thick]. This layer of endothelium acts as a barrier to blood, or anything in the blood, leaking from the lumen into the artery wall. There is a bit of space, sometime called the intima just under the endothelial cells.

The media: This layer is mostly made up smooth muscle cells and elastic tissue. The muscle can contract or relax, depending on circumstances

The adventitia: This outermost layer is mainly made up of collagen. It is very strong and keeps the artery in shape.

The atherosclerotic plaque: The areas of thickening and narrowing of arteries (in heart disease). These are usually found between the endothelium and the media – smooth muscle layer. They lie beneath the endothelium – within the artery wall itself. The area often referred to as the intimal layer of the artery.

The elevator pitch

Various people who work in business tell me of something called the ‘elevator sales pitch’. So-called, because of a (highly unlikely) situation whereby you find yourself in an elevator (which we in the UK call a lift) with a rich, famous, person. You have a short space of time to outline your idea to them, what it is, what it means, and why it is of value. They then hand over a hundred million dollars to invest in you, and your idea. Or something like that anyway.

Whilst the elevator pitch is clearly a mythical beast, the general point is reasonable. You should be able – or you should at least attempt – to condense your ideas into a very short space of time, before people get bored and walk away. Well, clearly I have miserably failed on this, as I am now writing part twenty-seven of my idea(s) on heart disease. In truth, I am planning on the elevator breaking down for about ten hours between floors to give me the time needed.

Recently, though, I have been speaking to a number of people who have successful careers in business, music, the arts and suchlike. I have been trying out my elevator pitch on them. Admittedly the elevator I am thinking of is in the Burj Khalifa in Dubai, but I am trying. So, here goes. Doors close on the elevator. Me and Bill Gates…

Me. ‘Forget diet, forget cholesterol, the real cause of heart disease is blood clotting.’

Bill Gates looks at his watch. ‘You have one minute.’

Me. ‘Blood clots can form and stick to the inside of artery walls. They then get absorbed into the artery wall itself where, normally, they are cleared away by specialised white blood cells. But if blood clots keep forming rapidly, at the same point, or the blood clots are bigger and more difficult to shift when they form, they cannot be cleared away quickly enough and so end up stuck inside the artery wall. This leads to a build-up of blood clot residue, and remnants, in the artery wall itself. Which means that repeated episodes of clotting, over time, build into thickenings, and narrow the larger arteries, mainly in the heart and the neck, growing somewhat like tree rings. These areas of damage are usually called atherosclerotic plaques.

In time, the process of blood clotting, over a vulnerable area, leads to heart attacks and strokes as the final, fatal blood clot forms over an area of the artery that is already thickened and narrowed. In short, atherosclerotic plaques are the remnants of blood clots. Heart attacks and strokes are the end result of the same processes that caused plaques to form in the first place. Heart disease is a disease of abnormal blood clotting. It is as simple as that. The end.’

Ping. Elevator door opens and Bill Gates walks out.

Do you think he believed me? Of course not. Heart disease is caused by cholesterol, end of.

Bill Gates: ‘Who was that complete idiot in the lift, make sure he never gets the chance to speak to me again.’

Man in black suit: ‘OK boss.’

I should point out that I have never spoken to Bill Gates, and almost certainly never will. I merely used his name as an example of someone that you might try to convince using an elevator sales pitch.

I also know that my sales pitch will just seem like the most complete nonsense to most people. How can I possibly claim that atherosclerotic plaques are blood clots, when no-one else in the entire world is saying it? Am I not simply a flat-Earther? Indeed, am I not a lonely flat-Earther baying at the moon. At least the moon currently passing overheard, to join all the other moons that clearly fall into a big basket on the other side of the Earth – to be returned from time to time by an enormous dung beetle.

I like to think not, because the ‘blood clotting’ hypothesis fits all known facts about cardiovascular disease. In fact, many people have proposed the ‘blood clotting theory’ of CVD over, what is now, hundreds of years. From Rokitansky to Duguid to Smith – and many more. Here, from a paper written in 1993 called ‘Fibrin as a factor in Atherosclerosis’, co-authored by Elspeth Smith.

[Just to first remind everyone that Fibrin is a critical element of blood clots (along with platelets). Fibrin is made up of short strings of a protein called fibrinogen. When the clotting system (clotting cascade) is activated, the end result is that fibrinogen is stuck together end to end, in order to create long sticky strands of fibrin that entangle themselves around the clot and bind it all together.]

‘After many years of neglect, the role of thrombosis in myocardial infarction is being reassessed. It is increasingly clear that all aspects of the haemostatic system are involved: not only in the acute occlusive event, but also in all stages of atherosclerotic plaque development from the initiation of atherogenesis to the expansion and growth of large plaques.

Infusion of recombinant tissue plasminogen activator (rt-PA) into healthy men with no evidence of thrombotic events or predisposing conditions elicited significant production of crosslinked fibrin fragment D-dimer. Thus, in apparently healthy human subjects there appears to be a significant amount of fibrin deposited within arteries, and this should give pause for thought about the possible relationship between clotting and atherosclerosis.

It also provides in vivo biochemical support for the numerous morphological studies in which mural fibrin and microthrombi have been observed adherent to both apparently normal intima and atherosclerotic lesions. It should be noted that these observations are based on the human and not just the animal model.

In 1852 Rokitansky discussed the “atheromatous process” (sic) and asked “In what consists the nature of the disease?” He suggests “The deposit is an endogenous product derived from the blood, and for the most part from the fibrin of the arterial blood”.

One hundred years later Duguid demonstrated fibrin within, and fibrin encrustation on fibrous plaques, and small fibrin deposits on the intima of apparently normal arteries. These observations have been amply confirmed but, regrettably, the emphasis on cholesterol and lipoproteins was so overwhelming that it was another 40 years before Duguid’s observations had a significant influence on epidemiological or intervention studies of haemostatic factors in coronary heart disease.’

Unfortunately, since that paper was written the emphasis on cholesterol and lipoproteins has become even more overwhelming, and research into blood clotting and atherosclerosis has faded to almost nothing. It appears that the vast sums of money to be made from cholesterol lowering has completely distorted research into this area. All the funding, and all the international experts, have charged into the blind-alleyway that is the cholesterol hypothesis.

In a kind of supreme irony, in 1992 Pfizer were also travelling down the blood clotting route. I have (mentioned before) possibly the only remaining copy of a small booklet entitled ‘Pathologic Triggers New Insights into cardiovascular risk.’ And I quote:

‘Several features of mature plaques, such as their multi-layered patterns, suggests that platelet aggregation and thrombus formation are key elements in the progression of atherosclerosis. Platelets are also known to provide a rich source of growth factors, which can stimulate plaque development.

Given the insidious nature of atherosclerosis, it is vital to consider the role of platelets and thrombosis in the process, and the serious events that may be triggered once plaque are already present.’

Of course, this leaflet was promotional, for their product doxazosin. Doxazosin lowers blood pressure and also has effects on urinary retention. However, in this leaflet, they were trying to promote its effects on blood clotting factors. Basically, doxazosin reduces fibrinogen levels and plasminogen activator inhibitor – 1 (PAI-1). Plasminogen is activated by tissue plasminogen activator (tPA) which then becomes plasmin, an enzyme that slices fibrin apart, and breaks down blood clots. PAI-1 stops this happening, so makes clots more difficult to break down.

To quote, again.

‘These recent studies suggest that doxazosin may have a range of significant antithrombotic effects in many patients, in addition to its proven beneficial effects on hypertension and hyperlipidaemia. Following doxazosin treatment, a reduction of platelet aggregation and a tendency towards dissociation, together with a reduction in fibrinogen levels, might prevent excessive degrees of thrombosis at the site of vascular injury. In addition, reduced levels of PAI-1, and increased tPA capacity with doxazosin might stimulate fibrinolysis and early clot dissolution at these sites, and prevent the evolution of an acute coronary event.’

So there, couldn’t have put it better myself.

Then Pfizer bought Warner-Lambert, who made atorvastatin/Lipitor. The focus became Lipitor and lipids, lipids, lipids. Lo it came to pass that Pfizer never mentioned blood clotting ever again, lest it interfere with the LDL story. Pity really, because mighty Pfizer got it right in 1992. Smith got it right in 1993, Duguid got it right in the 1940s, and Rokitansky was right in 1852. Of course, there have been many others who got it right too. Many, sadly, lost to history.

At some point this, the blood clotting hypothesis, the correct hypothesis will win. Maybe that time will be now.

Postscript

I realise some people may still wonder (if they have not read what I have written before) how the blood clot ends up within the artery wall/beneath the endothelium.

The reason is as follows. If the endothelium is damaged, a clot will form, sitting on the inside of the arterial wall. Once the clot has stabilised, and been reduced in size by fibrinolysis, the remainder of the clot will be covered over by Endothelial Progenitor Cells (EPCs) that float around in the bloodstream and are attracted to areas of endothelial damage.

After a layer of EPCs has grown over the clot, and converted themselves into mature endothelial cells the blood clot will now, effectively, be sitting inside the artery wall. Underneath a new layer of endothelium. Thus, clot becomes plaque.

http://circ.ahajournals.org/content /92/5/1355.full