A major row has erupted over conflict of interest claims involving a study linking negative news stories about statins with an increased risk of heart attacks and death.
One of the study's two authors, Danish scientist Professor Borge Nordestgaard, has admitted receiving consultancy fees and lecture payments from a host of drug companies.
Among them are AstraZeneca, Pfizer and Merck - all major producers of the cholesterol-lowering drugs taken by millions of people.
The disclosure, made in a brief conflict of interest statement at the end of the research paper, prompted a withering response from a doctors' leader.
Dr Kailash Chand, deputy chairman of the British Medical Association (BMA), said: "We need doctors to concentrate on research that matters to patients, not their careers or the advance of drug companies.
"The existence of a conflict of interest tends to create the appearance of bias even if the person with the conflict of interest acts completely impartially. In this study, the bias is very apparent."
Dr Chand, who was representing his own views and not those of the BMA, is an outspoken critic of what he regards as industry-driven hype surrounding statins.
The study is reported in the European Heart Journal, a highly respected publication, and was independently funded.
It is based on an analysis of data from 674,000 Danes aged 40 and over who were using statins between January 1995 and December 2010.
Their progress was followed until the end of 2011 and compared with trends in media coverage relating to statins.
The authors found a correlation between negative news stories about the medicines and people stopping their statin treatment within six months of a first prescription.
This in turn was associated a higher risk of heart attacks and deaths from cardiovascular disease.
Prof Nordestgaard, chief physician at Copenhagen University Hospital, said: "People who stop statins early have a 26 per cent increased risk of a heart attack and an 18 per cent increased risk of dying from cardiovascular disease when compared to people who continue to use them.
"Although we cannot say for sure that statin-related negative news stories cause the early discontinuation of statins, our findings suggest that this is likely. And although this type of association research cannot prove causality, our data suggest that early discontinuation of statins leads to unnecessary heart attacks and deaths from cardiovascular disease."
Statins are considered to be generally safe but can cause side effects in some patients including muscle pains and, rarely, a serious condition called rhabdomyolysis which destroys muscle fibres.
The other author who carried out the work with Prof Nordestgaard was Dr Sune Nielson, also from Copenhagen University Hospital.
Both made an obligatory conflict of interest statement at the end of the study. In relation to Dr Nielson, there were said to be "no financial or other conflicts of interest".
However, Prof Nordestgaard owned up to having received "consultancy fees and/or lecture honoraries" from AstraZeneca, Pfizer, Merck, Amgen, Sanofi, Regeneron, Omthera, Dezima, ISIS Pharmaceuticals, Aegerion, Fresenius, B. Braun, Kaneka, Lilly, Kowa and Denka Seiden.
Dr Chand argued the conclusions of the study were "very misleading" and detracted from the real issues surrounding statins - lack of transparency over the drugs' side effects and the fact that their benefits have been "grossly exaggerated".
