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

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 > or =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.