Prevalence of dyslipidemia in statin-treated patients in Canada: Results of the DYSlipidemia International Study (DYSIS)

BACKGROUND: Despite clear guideline recommendations, there is a growing body of evidence that there is suboptimal use of lipid-lowering treatment in Canadians. OBJECTIVE: To assess the prevalence and types of persistent lipid abnormalities in Canadian patients receiving statin therapy. METHODS: The present cross-sectional study recruited 2436 outpatients 45 years of age or older who were treated with statins by 232 physicians from 10 provinces; all underwent clinical examination and had their latest fasting lipid values while on statin therapy recorded. RESULTS: The median patient age was 66 years (interquartile range [IQR] 58 to 74 years), 60% were men and 80% were in the high 10-year risk category. The median low-density lipoprotein cholesterol level was 2.0 mmol/L (IQR 1.6 mmol/L to 2.5 mmol/L) and the median total cholesterol/high-density lipoprotein cholesterol ratio was 3.4 mmol/L (IQR 2.8 mmol/L to 4.1 mmol/L). However, based on the 2006 Canadian Cardiovascular Society recommendations, 37% of all patients did not have a low-density lipoprotein cholesterol level at goal or intervention target level, including 45% of high-risk category patients. The majority of patients received atorvastatin (50%) or rosuvastatin (37%) but primarily at low-to-medium doses, and a minority (14%) received additional lipid-modifying therapies. CONCLUSIONS: The present observational study highlights the need for more intensive treatment of lipid abnormalities, particularly among high-risk patients. Recognizing several important limitations related to the observational nature of the study, the findings suggest the possibility that, in addition to optimizing adherence, there remains an important need to titrate current statin therapy to higher doses and potentially use a combination of lipid-modifying treatments (once the statin dose has been truly maximized) to further bridge the gap between evidence-based medicine and current Canadian practice.