Harlan Krumholz is a professor of medicine and cardiologist at the at Yale University School of Medicine. He recently co-authored an open letter which appeared in the journal circulation (pdf here). The letter was written to the Adult Treatment Panel – a group of ‘experts’ charged with setting cholesterol guidelines for the American public. The panel is current considering this issue and is due to report later this year.
I suspect the panel, like a multitude of panels before it, will recommend that we keep strong downward pressure on our cholesterol numbers. But not all individuals in the medical and scientific community agree with this approach. One such dissenter is Professor Krumholz.
In this video below, Professor Krumholz does a good job, I think, of highlighting some of the major issues with current cholesterol policy. I advise you to watch the video but, for good measure, here’s a short summary of the salient points Professor Krumholz makes:
1. While targets are often based on levels of LDL-cholesterol, evidence shows that this is just one potential risk factor for cardiovascular disease. Many others exist, some of which are better predictors of cardiovascular disease than LDL-cholesterol.
2. Although it’s generally accepted that improvement in cardiac risk factors is beneficial, there is plenty of evidence that does not bear this out. He cites, for example, the example of the drug torcetrapib which lowered (supposedly unhealthy) LDL-cholesterol and raised (supposedly healthy) HDL-cholesterol. Torcetrapib, however, significantly increased overall risk of death in those who took it.
Professor Krumholz in his letter cites hormone replacement therapy as another example of a drug therapy that can ‘improve’ cholesterol numbers but that actually increases risk.
Other notable failures in terms of brining broad benefits to health include the drugs ezetimibe and fibrates.
3. Professor Krumholz speculates on why cholesterol ‘improvement’ may not actually improve health. One theory is that drugs which reduce cholesterol and have benefits (such as statins) do so through one or more mechanisms that are distinct from their cholesterol-lowering effects. Another is that even if cholesterol reduction is beneficial, this may be offset by the hazardous effects of a drug.
4. Professor Krumholz goes on to make the point that while we doctors are encouraged to treat peoples’ cholesterol down to a target level, not a single study has actually tested this approach.
5. He recommends an approach not based on cholesterol levels, but risk. He quite rightly points out that those at low risk of cardiovascular disease are unlikely to benefit much, but are still at risk of suffering from side-effects from treatment. He also points out the large ‘numbers needed to treat’ for relatively healthy people. Basically, about 50-100 people would need to be treated with a statin for 5 years to prevent on heart attack. This means, by the way, that 98-99 per cent of people treated will not benefit. People at higher risk stand to benefit more. However, it’s still true that the great majority who take statins will not benefit at all.
So there you have it, a neat summing up of the flaws in the conventional thinking regarding cholesterol lowering. And from a professor of medicine and cardiologist to boot. It’s a shame that the Professor Krumholz’s objectivity and ability to break out of the cholesterol ‘group-think’ is so rare in medicine. Many, many doctors would do well to follow his example.
His suggestions are very similar to current NICE guidance with regard to statins for primary prevention (ie those who have not had a cardiovascular event: assess cardiovascular risk; before offering statins, optimise other modifiable risk factors including smoking, blood pressure and glucose; do not offer fibrates, high intensity statins or combinations; there is no target level for total or LDL cholesterol for primary prevention and repeat lipid profile is not necessary.
Though when I tell my trainees that the effect of statins may occur through their anti-inflammatory action and not through cholesterol lowering, they look incredulous.
Many Thanks for sharing this Dr Briffa. It is reassuring to to know that not all of the “establishment” have their heads stuck where the sun don’t shine 😉 He presents a logical approach and I just hope he gains the ears of those who cam make a difference in the policies.
Dr. Devine, what is NICE?
Thanks for posting this John. I will pass it on to all I can. The word is getting out…drip by drip. You are a true water bearer.
What does he mean when he says LDL is a “risk factor”? Does he mean that it is a symptom or a marker for heart disease, in other words that there is a correlation? Or does he think that there is a causal relationship? It’s s shame he doesn’t say, because it is crucial to understanding whether to reduce LDL.
If LDL races into action to repair damage to the arteries, then there will be a correlation; but reducing it would have negative consequences (like arresting the fireman who arrive at the fire).
If, as I understand it, cholesterol acts as the body’s internal “scab” — patching up injuries to the arteries — then no wonder it doesn’t help to re
NICE stands for National Institute for Health and Clinical Excellence.
Dr Uffe Ravnskov,has been saying this for years.If you read his two books on Cholesterol you will get information overload but your eye’s well and truly opened.
So nice to hear a more balanced and thoughtful analysis getting heard. Yale is clearly getting back to developing good medicine. I recently heard a presentation at a conference by the Clinical Medicine professor at Yale on admitting Otto Warburg and his elucidation of the role of sugar in cancer was right (1925) and he now in his practise monitors sugars. The orthodox physician catches up slowly!!
Hooray for progressive Doctors and Researchers like Dr B and Prof Krumholz.
I’m doing a mind map at the moment of an interview with Chris Masterjohn about whole ‘cholesterol and heart disease’ issue. Very, very interesting. The best thing about the content so far is that Masterjohn seems happy to take a detached view of the science and talks about both sides of the argument with equal passion.
You can find the original interview (with Chris Kresser) here: http://chriskresser.com/the-healthy-skeptic-podcast-episode-11
And you can find the transcript of the interview here:http://blog.superbootcamps.co.uk/2012/diet-and-nutrition/the-healthy-skeptic-podcast-transcript-episode-11-chris-masterjohn-on-cholesterol-heart-disease-part-1/
Keep up the good work John
George
I fail to see what is that “dissent” that Krumholz is displaying. His case is about fine-tunig the current practises, not scrapping them. The man doesn’t deny the role of LDL-C as a risk factor, doesn’t deny the efficacy of statins in high risk primary prevention/secondary prevention etc. etc.
“While targets are often based on levels of LDL-cholesterol, evidence shows that this is just one potential risk factor for cardiovascular disease. Many others exist, some of which are better predictors of cardiovascular disease than LDL-cholesterol.”
Which is precisely the current message. Consider e.g. the classifications of different types of dyslipidemia.
“2. Although it’s generally accepted that improvement in cardiac risk factors is beneficial, there is plenty of evidence that does not bear this out.”
This is a case of interpreting the evidence in a – frankly put – silly fashion. Take, for example, torcetrapib. We know that it doesn’t work and have a pretty good idea why (for example, have a look at this: http://circ.ahajournals.org/content/118/24/2515.abstract). However, besides these, interventions aimed at also raising HDL-levels work (diet, exercise) and HDL levels are highly predictive of good cardiovascular health. See, for example, Barter et al ” HDL cholesterol, very low levels of LDL cholesterol, and cardiovascular events”, NEJM 2007.
“3. Professor Krumholz speculates on why cholesterol ‘improvement’ may not actually improve health. One theory is that drugs which reduce cholesterol and have benefits (such as statins) do so through one or more mechanisms that are distinct from their cholesterol-lowering effects. Another is that even if cholesterol reduction is beneficial, this may be offset by the hazardous effects of a drug.”
Former doesn’t seem very likely (for reasons I’ve already stated elsewhere), the former does.
“4. Professor Krumholz goes on to make the point that while we doctors are encouraged to treat peoples’ cholesterol down to a target level, not a single study has actually tested this approach.”
When talking about general population, this isn’t that far-fetched. However, with a proper diet & exercise and by avoiding tobacco and excess alcohol cholesterol levels are in order at any rate. Not to mention health benefits not related to cardiovascular health. Thus current guidelines bring broader benefits than just the cv-health issue. However, we do know that unfavourable lipid profile is a risk factor among others.
“5. He recommends an approach not based on cholesterol levels, but risk.”
Which, again, is not that different from what is recommended now.
How can healthy, unoxidized, LDL particles be bad? Their purpose is to deliver nutrients throughout our body.