Is conventional wisdom on cholesterol about to be turned upside down?

    14 June 2016

    New research has found no link between high levels of ‘bad’ cholesterol and mortality, challenging the prevailing wisdom of the past few decades.

    One author has claimed, too, that taking statins is a waste of time for those aged over 60 — though the research, published in the journal BMJ Open, did not look at the effectiveness of statins.

    A team of scientists reviewed 19 previous studies involving 68,000 people. They did not find a link between high levels of LDL cholesterol (or ‘bad’ cholesterol) and higher mortality rates — in some of the studies the opposite was the case.

    The researchers found that those with higher levels of LDL cholesterol actually lived longer. They suggested that the ‘bad’ cholesterol that statins are supposed to combat could play a role in preventing disease and infections.

    The authors said: ‘Our review calls for a re-evaluation of the guidelines for cardiovascular prevention, in particular because the benefits from statin treatment have been exaggerated.’

    One of the study’s authors, Dr Aseem Malhotra, said: ‘The scientific evidence clearly reveals that we must stop fear-mongering when it comes to cholesterol and heart disease and focus instead on insulin resistance, the most important risk factor as a precursor to many chronic diseases.’

    Professor Sherif Sultan, another co-author on the study, said: ‘Lowering cholesterol with medications for primary cardiovascular prevention in those aged over 60 is a waste of time and resources.’

    Instant analysis
    The study design was a systematic review, where similar studies are looked at within a specific framework in order to answer a particular clinical question. Statistical relationships are not established in the way they would be in a meta-analysis (the next step) and hence ‘overall’ results can only be discussed in general terms.

    Nineteen prospective cohort studies were selected with a total of 68,000 patients. Researchers looked at the relationship between blood levels of LDL-C, so-called ‘bad cholesterol’, and death, whether from cardiovascular disease or other causes.

    Fourteen of the studies found that lower LDL-C levels were associated with higher rates of death; the rest found no association between death rates and LDL-C levels.

    This paper is a potential game changer. It calls into question the traditional hypothesis that elevated LDL-C increases the risk of cardiovascular death that has been demonstrated in multiple other studies, and, at a simplistic level, whether or not the older population should even be on statins. I say potential, as the data needs to be collated and analysed statistically so that it can be compared directly to previous data.

    Take-home message: there is a current revolution within medicine regarding the traditional saturated fat/cholesterol hypothesis and the public should not be surprised at the claims and counter-claims in the press from various experts. Best to wait for the dust to settle.
    Research score: 4/5