Abstract 107: High Plasma Levels of Low-density Lipoprotein-cholesterol Accelerate Dissecting Aortic Aneurysms in Angiotensin II-induced Mice

Abstract Intorduction: Plasma levels of low-density lipoprotein cholesterol (LDL-C) are an important biomarker for coronary artery disease. In clinical and research settings worldwide, levels LDL-C are often not measured and are estimated using the Friedewald equation (total cholesterol - HDL cholesterol - triglycerides)/5). Bias of either over or underestimation of LDL-C can be corrected by direct measurement of LDL-C. We assessed the precision of the Friedewald equation in a heterogonous patients population within a wide range of lipid levels. Methods: A sample of consecutive fasting lipid profiles was obtained from ambulatory and hospitalized patients at the Chaim Sheba Medical Center, Tel-Hashomer. LDL-C concentrations were directly measured (dir LDL-C) (Olympus, Ireland) and correspondingly calculated at by the Friedewald equation (calc LDL-C). Results: 32,245 samples were analyzed. In 93% of the samples, underestimation of plasma levels of LDL-C was observed using the Friedewald equation. In 11,054 patients (34.3%), the difference between dir LDL and calc LDL were over 10mg/dl. In 7,693 patients (23.8%), the difference between dir LDL and calc LDL were over 20mg/dl. The difference between dir LDL and calc LDL correlated with plasma TG levels, including TG levels within the normal range. The difference between cal LDL and dir LDL levels is inversely correlated to cholesterol plasma levels. Conclusions: Direct measurement of LDL-C is more precise than Friedewald’s formula and overcomes the inaccurateness, due to elevated TG levels or relatively low LDL-C levels, in the setting of a heterogeneous Israeli population. In the era of extremely low LDL-C treatment goals, our findings require consideration due to their clinical importance and direct measurement of plasma LDL-C should be implemented as underestimation of LDL levels may lead to inappropriate therapeutic decisions.

Download Full-text

Regulation of plasma levels of low-density lipoprotein cholesterol: interpretation of data on low-density lipoprotein turnover in man.

Circulation ◽

10.1161/01.cir.74.4.805 ◽

1986 ◽

Vol 74 (4) ◽

pp. 805-814 ◽

Cited By ~ 24

Author(s):

J B Meddings ◽

J M Dietschy

Keyword(s):

Plasma Levels ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Lipoprotein Cholesterol ◽

Low Density ◽

Low Density Lipoprotein Cholesterol

Download Full-text

PCSK9 Levels and Metabolic Profiles in Elderly Subjects with Different Glucose Tolerance under Statin Therapy

Journal of Clinical Medicine ◽

10.3390/jcm10050994 ◽

2021 ◽

Vol 10 (5) ◽

pp. 994

Author(s):

Kari A. Mäkelä ◽

Jari Jokelainen ◽

Ville Stenbäck ◽

Juha Auvinen ◽

Marjo-Riitta Järvelin ◽

...

Keyword(s):

Glucose Tolerance ◽

Statin Therapy ◽

Plasma Levels ◽

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Lipoprotein Cholesterol ◽

Low Density ◽

Low Density Lipoprotein Cholesterol ◽

Statin Medication

Proprotein convertase subtilisin/kexin type 9 (PCSK9) degrades low-density lipoprotein cholesterol (LDL-C) receptors, and thus regulates the LDL-C levels in the circulation. Type 2 diabetics often have elevated LDL-C levels. However, the functions of PCSK9 in patients with alterations of glu-cose metabolism and statin therapy are still unclear. Method: we investigated a large cohort of 608 subjects, born in 1945 in Oulu, Finland (Oulu Cohort 1945). We studied the effects of PSCK9 lev-els with different glucose tolerances (normal glucose tolerance (NGT), prediabetes (PreDM) or type 2 diabetes (T2D)) with and without statin medication, and analyzed clinical data, NMR metabolomics and PCSK9 plasma levels. Results: PCSK9 plasma levels did not significantly differ between the three groups. Statin therapy significantly increased the PCSK9 levels in NGT, PreDM and T2D groups compared with subjects with no statins. In the NGT group, negative associations between PCSK9 and LDL-C, intermediate-density lipoprotein cholesterol (IDL-C), very low-density lipoprotein cholesterol (VLDL-C), total cholesterol and LDL and IDL triglycerides were observed under statin medication. In contrast, in the PreDM and T2D groups, these associa-tions were lost. Conclusions: our data suggest that in subjects with abnormal glucose metabolism and statin therapy, the significant PCSK9-mediated effects on the lipid metabolites are lost com-pared to NGT subjects, but statins reduced the LDL-C and VLDL-C levels.

Download Full-text