Aims: Guidelines for primary prevention of cardiovascular disease (CVD) with statins, including the most recent, fail to make the best use of the evidence from clinical trials by concentrating on absolute CVD risk as a statin indication and not also considering that a major determinant of therapeutic benefit is the magnitude of the low-density lipoprotein (LDL) (or non-HDL) cholesterol reduction achieved. This decrease is proportional to the pretreatment concentration. We set out to apply this knowledge to the calculation of the number needed to treat to prevent one event (NNT) and to assess critically how current guidelines performed at different degrees of CVD risk across a range of LDL (or non-HDL) cholesterol concentrations.
Methods and results: Number needed to treat to prevent one event revealed exclusion from the treatment of some people with higher cholesterol levels, who may benefit more than others needlessly exposed to statins with no realistic prospect of benefit. Furthermore, abandonment of cholesterol therapeutic goals disadvantaged people with higher levels.
Conclusion: These problems can be overcome by basing the decision to treat on the NNT calculated both from absolute CVD risk and also on the LDL (or non-HDL) cholesterol reduction achievable with statin treatment. This need not adds an additional layer of complexity for the clinician, because computer programmes already used to estimate CVD risk could be easily amended, thus permitting more effective deployment of statins in the population.
Keywords: Cardiovascular risk calculation; Number needed to treat; Primary prevention.
Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: [email protected].