A new analysis has looked at the considerations of whether and when statins may offer benefit beyond harm.
Within the UK, statins are the most commonly used drug. Over time, the number of people eligible for statin therapy has been widened through clinical guidelines.
Within their analysis, the authors explain the importance of interpretation of research data about statins.
They provide an example of two different people who might be prescribed statins to help explain how benefits of statins can widely vary between different individuals: “One is a 65 year old man who smokes, does not have heart disease, but who has high total cholesterol levels and raised blood pressure. The second is a 45 year old woman who does not smoke and has raised total cholesterol levels and slightly raised blood pressure.
“The man has an estimated 38% absolute risk of having a major coronary event in the next 10 years; the woman a 1.4% absolute risk.
“According to the risk reductions we reported, statins would reduce the man’s relative risk by 24% and the woman’s by 41%. However, the man could expect an absolute risk reduction of about 9% ([number needed to treat]=11) compared with just 0.6% ([number needed to treat]=166) for the woman.”
The authors use this to illustrate that while one statistic, reduction of relative risk, may appear to imply a significant benefit of statins for the woman, the absolute risk reduction actually suggests much lower benefit for the woman compared with the man.
Furthermore, treating 11 people exactly like the man would prevent one major coronary event, like a heart attack, from happening. By comparison, 166 women just like the woman in this example would need to be treated to prevent one major coronary event.
The analysis notes that questions remain as to how much bias may exist within reporting of clinical trial data. They raise the possibility that, “studies reporting results that are favourable to the pharmaceutical industry may be more likely to be published and may under-report harms.”
The authors express caution in widening the availability of statins, stating: “Although statins are commonly prescribed, serious questions remain about their benefit and acceptability for primary prevention, particularly in patients at low risk of cardiovascular disease.”
They suggest that in low-risk individuals, statins “may be an example of low value care” and may, in some individuals, “represent a waste of healthcare resources”.
In closing, the analysis calls for better data to be available on the potential harms of statins and the outcomes related to people at low risk of cardiovascular problems.
The analysis is published in the journal, BMJ.