Patrick Holford distorts research findings on statins to push his pills
Posted by gimpy on September 7, 2008
I am a masochist. This is why I signed up for ex-Visiting Professor Patrick Holford’s health e-news bulletins. Normally these emails consist of a plug for some dubious piece of pseudo-scientific equipment or vitamin supplements from one of the companies Patrick has a financial interest in. However, sometimes you get his thoughts on a new scientific study or perhaps an attack on one of his many critics. These type of things are usually covered by the always admirable Holfordwatch but Patrick does produce a surfeit of nonsense so this time round I think I will deal with it.
The latest email from Patrick Holford comes with the provocative title “Omega 3’s, not Statins, Cut Risk of Heart Deaths” and the opening paragraphs are as follows:
Fish oils are better than cholesterol-lowering statin drugs. That’s the conclusion of two long-term studies, published this week in the Lancet medical journal. The studies compared the effects of giving patients with heart failure cholesterol-lowering statin drugs or omega 3 fish oils versus placebo. Those given omega 3 fats had a significantly reduced risk of death or hospitalisation, while the statin drugs had no effect. Those taking 1 gram a day of omega 3 fats cut their risk of mortality by 9% and risk of admission to hospital by 8% compared to placebo. Those taking statins had no reduction in risk after almost four years on the drug.
This adds to the weight of evidence in favour of upping omega 3 intake, both from diet and supplements. Taking 1 gram of omega 3 fish oil a day, as given in this study, is equivalent to eating a serving of oily fish almost every day.
It also confirms growing evidence of ineffectiveness of statin drugs in reducing mortality, both in healthy people and those with heart failure. A previous meta-analysis of trials giving statins to healthy people found no difference in mortality after almost four years use.
This sounds like vindication of some of Patrick’s advice to take (his) fish oil pills in a bid to improve health. However, regrettably Patrick did not provide references for his claims so readers of his emails, even if they had a The Lancet subscription, are not able to check his claims. For those who are interested the papers are as follows:
Effect of rosuvastatin in patients with chronic heart failure (the GISSI-HF trial): a randomised, double-blind, placebo-controlled trial.
Effect of n-3 polyunsaturated fatty acids in patients with chronic heart failure (the GISSI-HF trial): a randomised, double-blind, placebo-controlled trial.
Also this research has been covered in this in depth article from Medscape and the essential ‘Behind the Headlines’ NHS blog. I will be using these publicly available articles for my analysis of Patrick’s claims.
So does the evidence support Patrick’s claims? Not exactly. The Behind the Headlines blog reports the trial as follows:
The absolute benefits are small and the oils in this study were taken at the same time as standard treatments for heart failure. These treatments (including β-blockers and ACE-inhibitors) have proven clinical benefit of a magnitude far greater than that seen with omega-3 oils here.
The researchers note that after two years of treatment, differences were evident in all-cause mortality and hospitalisation for cardiac reasons between the two groups. Death from any cause occurred in 27% taking n-3 PUFA and in 29% taking the placebo. Absolute risk of death was reduced by 1.8% (95% CI 0.3% – 3.9%). There was a difference in rate of all-cause death or admission to hospital for cardiac causes between the groups: 57% with n-3 PUFA versus 59% with placebo – this reduction in risk was only of borderline statistical significance. There were no differences in rates of sudden cardiac death between the groups, in numbers with heart attack or stroke or in presumed arrhythmic death or from worsening heart failure.
This is not consistent with Patrick’s claims of a 9% reduction in mortality and a 8% reduction in hospital admissions. So where did these figures come from? The Medscape article reports:
After 3.9 years of follow-up, treatment with the omega-3 fatty acids reduced the risk of mortality by 9% and mortality and admission to the hospital for cardiovascular causes by 8%. The absolute reduction in risk was small, just 1.8%, but investigators report that 56 patients would need to be treated to avoid one death and 44 patients would need to be treated to avoid one death or admission for cardiovascular reasons. A per-protocol analysis that included only patients who remained on treatment for the study duration confirmed the overall findings, showing that treatment cut the absolute risk by 3.3% compared with placebo, or a 14% relative risk reduction.
This is presumably the source for Patrick’s figures. Patrick it seems has opted for relative risk, the percentage difference in mortality between the omega-3 and placebo groups, not the absolute risk, the decreased risk of mortality in the between the two groups over time. A detailed explanation of relative vs absolute risk can be found from Patient UK which has the following quote:
Many reports in the media about the benefits of treatments present risk results as ‘relative risk’ reductions rather than ‘absolute risk’ reductions. This often makes the treatments seem better than they actually are.
It seems Patrick is guilty of this. However Patrick is partially correct in pointing out that a statin, rosuvastatin, (not statins in general) has no effect on heart-failure patients over the study duration in terms of mortality and hospital admission. But his claims that this is true in healthy patients as well are inaccurate as this wasn’t assessed by the trial, in fact Medscape reports the study authors make the point:
[...]that treatment with rosuvastatin reduced LDL cholesterol as well as high-sensitivity C-reactive protein (CRP) levels. “These effects might no longer affect the progression of coronary artery disease in patients with ischemic heart failure, perhaps because their effect is attenuated by a biological milieu not favoring the progression of coronary artery disease,” they write in the Lancet. [...]once heart failure is established, statins may not allow patients to escape the underlying heart-disease process.
In other words once you have heart failure statins may become ineffective, the researchers make no comment on the benefit of statins in healthy patients. This lack of focus on healthy patients makes the next claim from Patrick quite extraordinary.
Despite growing evidence of ineffectiveness the UK government remain committed to prescribing statins to millions of people, and GPs are financially rewarded for doing so. In the US there is a move to prescribe statins to 8 year olds as a preventative measure against future heart disease.
While there is some debate over the use of statins the evidence for their effectiveness in improving health is overwhelming. It is ludicrous to imply that GPs prescribe statins, based not on evidence, but handouts from Big Pharma. Patrick it seems has both an aversion to statins and a strong belief that drug companies are distorting evidence to promote their own products. Of course some drug companies are distorting some evidence to promote their products and this is a Bad Thing. However, one of the methods around this is to insist on a full disclosure of interests. This is why it is heartening to find out that the study that found no benefit to rosuvastatin, a drug made by AstraZeneca, in heart patients comes with the following disclosure:
LT, GT, APM, RM, and MGF received research support and honoraria for lectures from AstraZeneca. GLN and MP received honoraria for lectures from AstraZeneca. RL, SB, and DL received research support from AstraZeneca.
A welcome example of a drug company making clear the circumstances where their drug does not work. Now why would someone like Patrick distort evidence, disregard the fact that both groups were on highly effective medicine against heart conditions and decry mainstream medicine as being corrupt and in the pocket of big pharma? Could it have anything to do with the fact that Patrick reaps considerable financial benefit from his association with the nutritional supplement industry?
There is clear evidence that there is a mild benefit to be gained by heart patients taking omega-3′s and that these patients do not benefit from rosuvastatin. But as all the patients in the study were on other medications of far greater benefit than omega-3′s it is perverse to use these studies to criticise medical interventions and put doubt in the minds of people as to the benefit of drugs. Patrick Holford is a parasite on society who is taking financial advantage of concerned customers by repeatedly distorting scientific evidence to push his own pills and harming the public’s understanding of science.