In a public lecture hosted by the British Association for Psychopharmacology and Bristol’s MRC Integrative Epidemiology Unit (where I work), Professors George Davey Smith and David Nutt stripped away the sensationalisation and misinformation around statins and SSRIs. They come from very different fields, George is an epidemiologist and David a psychiatrist, but both fields can help us understand the efficacy and safety of drug treatments.
George took on the topic of statins. George is a perfect example of a scientist being led by the evidence - he himself wrote an article 25 years ago calling for cholesterol lowering drugs to cease to be prescribed, but now believes the evidence is overwhelming in support of the use of statins for lowering cholesterol, which reduces the risk of cardiovascular disease. Not that you’d necessarily see that from the media, where their use has been linked to everything from baldness to memory loss, kidney damage to nosebleeds.
Statins are now probably the most intensively investigated drug in medicine, with huge number of randomised trials examining their effectiveness, and their side effects. The recent Cochrane collaboration meta-analysis of all the trials investigating statins conducted by 2013, indicate that for those at low to moderate risk of a heart attack (men over 50 with high blood pressure, but not those who have already suffered heart problems), 18 of 1000 treated for 5 years would avoid a major cardiovascular event due to taking the statins. In those who have already had a heart attack, the protective effect of statins is 10 times greater.
Of course, no drugs are without any side effects. And a lot of the media reports of statins being associated with various negative outcomes might be true, but they fail to point out that associations of the same size are seen in the control group – the nocebo effect. There is evidence that risk of diabetes might be slightly increased by statins, but other than that the side effects are very small compared to placebo.
George described a neat method for ascertaining whether statins were associated with myalgia – muscle pain - as this was a commonly complained of side effect. In order to test whether certain individuals really were suffering these adverse reactions because of statins, they acted as their own controls. Their statins were replaced every so often with an identical sugar pill, and reports of myalgia were recorded. Participants in these ‘n-of’1’ trials didn’t suffer myalgia more when they were taking statins compared to sugar pills, suggesting that it’s not the statins causing the muscle pain.
Looking to the future, George, while cautioning against being too optimistic just yet about personalised medicine, pointed to genetic information as a way of looking for drug targets. If genetic variation is associated with a disease, then the genetic differences between the groups could suggest mechanisms for drugs to target.
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