Limitations of statin monotherapy for the treatment of dyslipidemia: a projection based on the Canadian lipid study – observational

ABSTRACT

Objective: Several randomized controlled trials indicate that a low density lipoprotein cholesterol (LDL-C) target <2.0 mmol/L is appropriate for individuals at high risk of coronary artery disease (CAD). Recently released Canadian lipid management guidelines (2006) have incorporated this evidence into their recommendations. A cross-sectional study of patients treated with statins for at least 8 weeks (CALIPSO) was used as a basis to project the ability of statin monotherapy in getting high CAD-risk patients to an LDL-C level <2.0 mmol/L.

Research design and methods: The analysis was restricted to CALIPSO patients on statin monotherapy who were at high CAD-risk (including patients with established CAD). Assuming all patients could have their statin titrated up to the maximum dose, the proportion of patients that would reach an LDL-C level of <2.0 mmol/L was projected. To do this, the additional LDL-C reduction patients would achieve with maximal titration of their statin was estimated based on a meta-analysis of clinical trials evaluating LDL-C responses to various statin regimens, and applied to patients’ current LDL-C level.

Results: A total of 1795 high CAD-risk patients treated with statin monotherapy were included in the analysis, of whom 69.8% had an LDL-C ≥2.0 mmol/L. Depending on the statin that was used, it was projected that between 28.2% and 62.7% of high CAD-risk patients would not attain an LDL-C of <2.0 mmol/L following statin titration to maximum dose.

Conclusions: Although the accuracy of our projections may be limited by the application of clinical trials data to an external sample of patients, our results suggest that for 38% of patients at high CAD-risk, titration of statin monotherapy will not be sufficient to achieve an LDL-C target of <2.0 mmol/L. For these patients, additional treatment approaches may be needed to further reduce the risk of coronary events.

Key words: :

• Dyslipidemia management
• Hypercholesterolemia
• LDL-C
• Lipoproteins
• Statins

Acknowledgements

Declaration of interest: This study was funded by Merck Frosst Schering Pharmaceuticals, Montreal, Canada. Fig.P Software Inc. was hired by Merck Frosst Schering Pharmaceuticals to collect and manage the study data. Peter Melnyk, BioMedCom Consultants Inc., provided editorial assistance in the preparation of this manuscript. R.J.S is the president of Fig.P Software, and M.S. and M.M. are employees of Merck Frosst Canada Ltd. G.F. holds grants from the Canadian Institute of Health Research and Ontario Heart and Stroke Foundation and holds a research grant from AstraZeneca. In the past 5 years G.F. has received grants from Merck and Pfizer and speaker fees from Merck and Schering-Plough. C.G. and R.M. have served on advisory boards and received speaker honoraria from Merck Frosst Schering Pharmaceuticals, Pfizer and AstraZeneca. C.G. has received speaker honoraria from Merck Frosst Canada as well. J.G. has received grants, consulting and speaker honoraria, or has served on advisory boards for Aventis, Astra Zeneca, Merck-Frosst, Schering Plough, Pfizer, Novartis and Resverlogix. M.-A.L. has received speaker or consultant honoraria from Schering-Plough, Merck Frosst Schering Pharmaceuticals and Merck Frosst Canada.