Prevalence of mixed dyslipidemia among Australian patients undergoing lipid-modifying therapy

BACKGROUND: Few studies have assessed the prevalence of mixed dyslipidemia (MD) and the effectiveness of lipid-modifying therapy (LMT) for the treatment of abnormal levels of low-density lipoprotein cholesterol (LDL-C), triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C) in Australian clinical practice. OBJECTIVE: To estimate the prevalence of MD in Australian patients undergoing LMT. METHODS: Patients 35 years of age and older undergoing LMT for >= 1 year were enrolled from nine general practice and cardiologist/endocrinologist outpatient clinics in Australia between April 2007 and May 2008. Lipid levels, including LDL-C, HDL-C and TG levels, were prospectively collected at the enrollment date and from patient records one year before LMT was initiated. Normal lipid levels were assessed according to Australian guidelines. Multivariate logistic regression was used to evaluate predictors of normal lipid level attainment. RESULTS: Of 297 patients (mean age 60.1 years; 43% male), the prevalence of MD before LMT was 61%; 93% of patients had elevated LDL-C levels, 17% had low HDL-C levels and 62% had elevated TG levels. Following LMT (98.3% statins), 31% of patients had MD. The prevalence of elevated LDL-C levels, low HDL-C levels and elevated TG levels were 44%, 21% and 42%, respectively. Baseline lipid levels were significant predictors of attainment of normal LDL-C levels (OR 0.42 [95% CI 0.27 to 0.63]) and TG levels (OR 0.26 [95% CI 0.16 to 0.45]). CONCLUSION: Among Australian patients primarily treated with statins, nearly one-third had MD despite LMT. LMT considerably improved LDL-C goal attainment; however, a large proportion of patients did not achieve normal HDL-C and TG levels. Patients may benefit from a more comprehensive approach to lipid management that treats all three lipid risk factors, as suggested in clinical guidelines.