Questioning the benefits of statins

Eddie Vos and Colin Rose are concerned that we overestimated the benefit of statins in women and older people in our analysis1 of the Canadian recommendations for dyslipidemia management.2 On the other hand, Jacques Genest and colleagues accused us of underestimating the benefit of statins.3 Others suggest that statins have a small or no relative benefit in people at low risk of developing cardiovascular disease.4

Debates about the relative benefit of statins are welcomed but do not change the main findings of our analysis, because a patient's underlying risk of cardiovascular disease is in many cases more important than the precise relative risk reduction.5 Statins have a very small absolute benefit in people at low risk and a very high absolute benefit in people at high risk. The 2003 Canadian dyslipidemia guidelines2 inappropriately fail to recommend treatment of many Canadians at the highest risk of developing cardiovascular disease while recommending treatment of markedly more individuals at low risk.

If we assumed a higher relative benefit of statins in our analysis, as Genest and colleagues suggested, it would be even more apparent that the guidelines should recommend treatment to people at high risk who are not currently offered statins. However, because the baseline risk of death is very small in groups at low risk of developing cardiovascular disease, even with a higher relative benefit of statins very few deaths would be avoided in these people. If we assumed a lower relative benefit of statins, as Vos and Rose suggest, the absolute benefit in populations at low risk would no longer be extremely small (as we found in our original analysis) but would be virtually undetectable, or statin therapy would possibly even have to be considered harmful. In the end, the take-home message remains the same: statins are beneficial in people at high risk of cardiovascular disease and not clinically important in those at low risk.