Wednesday, May 21, 2014

Dr John Briffa's response to the BMJ's withdrawal of comments.

My reaction to the BMJ’s withdrawal of statements relating to the safety of statins

You may have noticed that there’s a bit of a ‘fight’ going on over the cholesterol-reducing class of drugs known as ‘statins’. I am simplifying here, but there are essentially two opposing camps. In one corner, there are those doctors and researchers who hold the view that the statins should be given to pretty much all adults from middle-age, and there is little to be concerned with regarding their safety. In the other corner, there are those who believe that statins do no good at all for the vast majority of people who take them, and that the side-effects are more common that ‘official statistics’ suggest.
The fight went up a notch last week when the editor of the British Medical Journal announced that remarks made in two BMJ articles about the side-effects of statins had been withdrawn [1]. One of the articles was written by Dr John Abramson from Harvard Medical School and colleagues, and principally questioned whether extending statin use to those at lower risk (as has been suggested by the National Institute of Health and Care Excellence) will save lives [2].  According to their analysis, it won’t. The other piece was written by UK cardiologist Dr Aseem Malhotra, and principally questioned the role of saturated fat in heart disease [3].

In both articles, the authors referred to a study [4] that found that 17.4 per cent of people taking statins had adverse effects as a result attributed to statins. In the articles this figure was expressed as 18 per cent or ‘about 20 per cent’ which, apparently, was the first error. However, other issues, according the BMJ, was that the authors claimed that the 17.4 figure related to the percentage of people who stopped statins (at least temporarily) due to side-effects – this is not correct (it represented the percentage of people who had adverse effects). Also, the study in question was ‘observational’ in nature, which means that we don’t know if the adverse effects are due to statins or are the result of the ‘nocebo’ effect (like a placebo effect, only with negative effects rather than positive). The Editor of the BMJ, Fiona Godlee, tells us in her editorial that the caveats concerning the observational nature of these findings should have been made.

Both the articles made it through the peer-review process, so how did these errors come to be picked up? Well, apparently, they were brought to the attention of Fiona Godlee by Professor Sir Rory Collins, who heads up what is known as the Cholesterol Treatment Trialists (CTT) collaboration based in Oxford, UK. The CTT holds data on statin studies and periodically assesses it to tell us that statins are safe and very effective.

However, the CTT has in the past made grand claims about the effectiveness of statins that are based on the extrapolation of data (rather than actual data). Plus, as some have pointed out, the CTT refuses to release its data for independent inspection. The CTT can basically say what it likes about the effectiveness and safety of statins, but no-one can challenge what it says because no-one else has access to its data.

Apparently, Professor Sir Collins was invited by Fiona Godlee to put his concerns in writing for publication but he refused. He and Fiona Godlee met, and this set the ball rolling which culminated in the withdrawal detailed above. However, apparently this is not enough for Professor Sir Collins: he is demanding retraction of both articles, even though he has not challenged the main points raised in the articles. Fiona Godlee has set up an investigation to determine whether or not the articles should be retracted.

I have written to the BMJ in the form of an online ‘rapid response’ that was posted yesterday. You can read my response here.

In my response I accept that errors were made, but ask if a simple correction might have done.
Professor Sir Collins bases his assertions regarding the safety of statins on data from randomised controlled trials, like the ones analysed by the CTT. However, there are many reasons why randomised controlled trials may not adequately identify and report adverse effects from statins. Fiona Godlee acknowledges this herself and lists some of the issues, and I add to that list in my response. In all, there are about a dozen reasons why randomised trials stand to ‘miss’ adverse effects.

I also raise the issue of a recent study which appeared to confirm the safety of statins [5]. The study also detailed many reasons why results from clinical trials are an unreliable assessor of side effects. The study was reported in the BMJ [6], but the report included none of the caveats listed in the paper (or any other ones). As I explain to the Editor, these omissions may lull individuals into a false sense of security, and put people at unnecessary risk of adverse effects of statins, some of which can be serious.

One might argue that the ‘crime’ committed by the BMJ is roughly equivocal to the ones perpetrated by Drs Abramson and Malhotra. I point this out to Fiona Godlee in my response, and request a meeting with Fiona Godlee to discuss my concerns. After all, why should I not be afforded similar privileges as Professor Sir Collins”

You can read the response in full here. If you agree with the sentiments expressed in it, please click on the ‘thumbs up’ symbol to the right of the response to log your agreement.

References:
1.    Godlee F. Adverse effects of statins. BMJ 2014;348:g3306
2.    Abramson JD, Rosenberg HD, Jewell N, Wright JM. Should people at low risk of
cardiovascular disease take a statin? BMJ2013;347:f6123

3.    Malhotra A. Saturated fat is not the major issue. BMJ2013;347:f6340
4.   Zhang H, et al. Discontinuation of statins in routine care settings. Ann Intern Med 2013;158:526-34
4.    Finegold JA, et al. What proportion of symptomatic side effects in patients taking statins are genuinely caused by the drug? Systematic review of randomized placebo-controlled trials to aid individual patient choice. European Journal of Preventive Cardiology 2014;21(4):464-74
5.    Wise J. Statins may have fewer side effects than is claimed, meta-analysis finds BMJ 2014; 348:g2151
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Read the complete article here.

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