Laboratory Medicine and Quality Assurance

Korean Association of External Quality Assessment Service (대한임상검사정도관리협회)
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Factors Affecting the Difference between the Low-Density Lipoprotein Cholesterol Concentrations Measured Directly and Calculated Using the Friedewald Formula

직접 측정한 저밀도지단백 콜레스테롤과 계산한 저밀도지단백 콜레스테롤의 차이에 영향을 주는 요인

Min, Won-Ki;Park, Hae-Il;Jun, Kyung-Ran;Chun, Sa-Il;Lee, Woo-Chang
민원기;박해일;전경란;전사일;이우창

  • Published : 20080000
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Abstract

National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) is the guideline for detection evaluation, and treatment of high blood cholesterol in adults. The risk of coronary heart disease (CHD) is assessed by the presence of CHD risk equivalents and the number of risk factors. LDL-cholesterol is the goal of treatment for hyperlipidemia. Contents:The most common approach for determining LDL-cholesterol level in clinical laboratory is to calculate it based on Friedewald formula. For accurate risk assessment by the calculated LDL-cholesterol, good analytical performances of total cholesterol, HDL-cholesterol and triglyceride are prerequisite. Even if the analytical performance of these three analytes are within the acceptable criteria, pooled imprecision and bias of the calculated LDL-cholesterol could not meet the criteria for LDL-cholesterol. Even under conditions satisfying the requirements of Friedewald formula, the calculated LDL-cholesterol level was lower than the directly measured level and the difference was dependent on the level of triglyceride, LDL-cholesterol and total cholesterol. When evaluatingpatients with hyperlipidemia, Friedewald calculation may underestimate the risk for coronary heart disease which may lead to inappropriate treatment option.

Keywords

References

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