Comparison of LDL-Cholesterol direct measurement with the estimate using various formula

( Se Young Kwon ),( Young-ak Na ) 대한임상검사과학회 2012 대한임상검사과학회지(KJCLS) Vol.44 No.3

Low-Density Lipoprotein cholesterol (LDLC) is the most important marker for the treatment of hyperlipidemiain NCEP-ATP III(National Cholesterol Education Program-Adult Treatment Panel III) guideline. Therefore, LDL cholesterol is pathologically meaningful, accurate measurement should be a top priority. Currently, LDLC is directly measured in most cases, but, the estimate is still used in mass health examination or screening test. This study is about the comparison of LDL-Cholesterol direct measurement with the estimate using various formula (Friedewald: [LDL-F=TC-HDL-TG/5], Nakajima: [LDL-N=TCHDL- TG/4], Hattori: [LDL-H =0.94TC -0.94HDL-0.19TG], Puavilai: [LDL-P=TC-HDL-TG/6], Carvalho: [LDL-C=3(TC-HDL)/4]) for calculating more accurate value. We analyzed total cholesterol (TC), tryglyceride (TG), high-density lipoprotein cholesterol (HDLC), and LDLC levels of 210 subjects between June and November in 2011. Until now, the Friedewald formula is the most commonly used estimate for the LDLC. When Friedewald formula was applied, the correlation coefficient (r) was 0.940, showing high correlation. But, the result of the direct method was significantly different, compared with those of the Friedewald formula in triglyceride levels≥400 mg/dL(p<0.05). There was the highest correlation when we used LDL-P formula(r=0.947) in triglyceride levels <400 mg/dl. Also there was the lowest mean difference regardless of triglyceride level. Therefore, the study showed that TG/6 is more precise means of calculation than TG/5. On the other hand, the calculation of LDL-Cholesterol was underestimated, compared with direct measurement. It is necessary to have more data and modified Friedewald formula should be used for the accurate calculation.

Validity for Use of Non-HDL Cholesterol Rather than LDL Cholesterol

( Se-young Kwon ),( Young-ak Na ) 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.2

NonHDL cholesterol values have been suggested as a risk marker for cardiovascular disease. NonHDL cholesterol values were calculated, using a very simple measurement [nonHDL cholesterol =serum total cholesterol-HDL cholesterol]. This formula is very useful as a screening tool for identifying dyslipoproteinemias, risk assessment, and assessing the results of hypolipidemic therapy. The data from the 2009 Korean National Health and Nutrition Examination Survey were used. Analysis was done for 1,992 subjects with lipid panels (Cholesterol, HDL, LDLdirect and Triglycerides) results. We studied the relationship between nonHDL cholesterol and LDL cholesterol. As a result, nonHDL cholesterol values were plotted against the LDL direct and calculated values. The linear regression equation for nonHDL cholesterol and direct LDL cholesterol was nonHDLchol=23.60+1.03×LDLdirect (p<0.0001, r2=0.80) in all subjects. The subjects were classified into triglyceride values. When triglycerides are below 400 mg/dL, the linear fit to LDL direct is found to be [nonHDLchol=17.34+1.07×LDLdirect] (p<0.0001, r2=0.88) and to the Friedewald LDL calculation is [nonHDLchol=23.10+1.02×LDLcalc] (p<0.0001, r2=0.82). For triglycerides above 400 mg/dL, the linear fit equation is [nonHDLchol=87.57+0.92×LDLdirect] (p <0.0001, r2=0.50) and to the LDL calculated, it is [nonHDLchol=142.70+0.50×LDLcalc] (p <0.0001, r2=0.32). This study provides examples of the utility of nonHDL cholesterol concentrations in clinical medicine.

오히려 LDL 콜레스테롤 보다 비 HDL 콜레스테롤을 사용하는 것의 타당성

권세영,나영악 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.2

NonHDL cholesterol values have been suggested as a risk marker for cardiovascular disease. NonHDL cholesterol values were calculated, using a very simple measurement [nonHDL cholesterol =serum total cholesterol-HDL cholesterol]. This formula is very useful as a screening tool for identifying dyslipoproteinemias, risk assessment, and assessing the results of hypolipidemic therapy. The data from the 2009 Korean National Health and Nutrition Examination Survey were used. Analysis was done for 1,992 subjects with lipid panels (Cholesterol, HDL, LDLdirect and Triglycerides) results. We studied the relationship between nonHDL cholesterol and LDL cholesterol. As a result, nonHDL cholesterol values were plotted against the LDL direct and calculated values. The linear regression equation for nonHDL cholesterol and direct LDL cholesterol was nonHDLchol=23.60+1.03×LDLdirect (p<0.0001, r2=0.80) in all subjects. The subjects were classified into triglyceride values. When triglycerides are below 400 mg/dL, the linear fit to LDL direct is found to be [nonHDLchol=17.34+1.07×LDLdirect] (p<0.0001, r2=0.88) and to the Friedewald LDL calculation is [nonHDLchol=23.10+1.02×LDLcalc] (p<0.0001, r2=0.82). For triglycerides above 400 mg/dL, the linear fit equation is [nonHDLchol=87.57+0.92×LDLdirect] (p <0.0001, r2=0.50) and to the LDL calculated, it is [nonHDLchol=142.70+0.50×LDLcalc] (p <0.0001, r2=0.32). This study provides examples of the utility of nonHDL cholesterol concentrations in clinical medicine.

Validity for Use of Non-HDL Cholesterol Rather than LDL Cholesterol

Kwon, Se-Young,Na, Young-Ak 대한임상검사과학회 2013 대한임상검사과학회지(KJCLS) Vol.45 No.2

NonHDL cholesterol values have been suggested as a risk marker for cardiovascular disease. NonHDL cholesterol values were calculated, using a very simple measurement [nonHDL cholesterol=serum total cholesterol-HDL cholesterol]. This formula is very useful as a screening tool for identifying dyslipoproteinemias, risk assessment, and assessing the results of hypolipidemic therapy. The data from the 2009 Korean National Health and Nutrition Examination Survey were used. Analysis was done for 1,992 subjects with lipid panels (Cholesterol, HDL, LDLdirect and Triglycerides) results. We studied the relationship between nonHDL cholesterol and LDL cholesterol. As a result, nonHDL cholesterol values were plotted against the LDL direct and calculated values. The linear regression equation for nonHDL cholesterol and direct LDL cholesterol was $nonHDLchol=23.60+1.03{\times}LDLdirect$ (p<0.0001, $r^2=0.80$) in all subjects. The subjects were classified into triglyceride values. When triglycerides are below 400 mg/dL, the linear fit to LDL direct is found to be $[nonHDLchol=17.34+1.07{\times}LDLdirect]$ (p<0.0001, $r^2=0.88$) and to the Friedewald LDL calculation is $[nonHDLchol=23.10+1.02{\times}LDLcalc]$ (p<0.0001, $r^2=0.82$). For triglycerides above 400 mg/dL, the linear fit equation is $[nonHDLchol=87.57+0.92{\times}LDLdirect]$ (p<0.0001, $r^2=0.50$) and to the LDL calculated, it is $[nonHDLchol=142.70+0.50{\times}LDLcalc]$ (p<0.0001, $r^2=0.32$). This study provides examples of the utility of nonHDL cholesterol concentrations in clinical medicine.

Comparison of LDL-Cholesterol direct measurement with the estimate using various formula

Kwon, Se Young,Na, Young-Ak 대한임상검사과학회 2012 대한임상검사과학회지(KJCLS) Vol.44 No.3

Low-Density Lipoprotein cholesterol (LDLC) is the most important marker for the treatment of hyperlipidemia in NCEP-ATP III(National Cholesterol Education Program-Adult Treatment Panel III) guideline. Therefore, LDL cholesterol is pathologically meaningful, accurate measurement should be a top priority. Currently, LDLC is directly measured in most cases, but, the estimate is still used in mass health examination or screening test. This study is about the comparison of LDL-Cholesterol direct measurement with the estimate using various formula (Friedewald: [LDL-F=TC-HDL-TG/5], Nakajima: [LDL-N=TC-HDL-TG/4], Hattori: [LDL-H =0.94TC-0.94HDL-0.19TG], Puavilai: [LDL-P=TC-HDL-TG/6], Carvalho: [LDL-C=3(TC-HDL)/4]) for calculating more accurate value. We analyzed total cholesterol (TC), try-glyceride (TG), high-density lipoprotein cholesterol (HDLC), and LDLC levels of 210 subjects between June and November in 2011. Until now, the Friedewald formula is the most commonly used estimate for the LDLC. When Friedewald formula was applied, the correlation coefficient (r) was 0.940, showing high correlation. But, the result of the direct method was significantly different, compared with those of the Friedewald formula in triglyceride levels ${\geq}400mg/dL$(p<0.05). There was the highest correlation when we used LDL-P formula(r=0.947) in triglyceride levels <400 mg/dl. Also there was the lowest mean difference regardless of triglyceride level. Therefore, the study showed that TG/6 is more precise means of calculation than TG/5. On the other hand, the calculation of LDL-Cholesterol was underestimated, compared with direct measurement. It is necessary to have more data and modified Friedewald formula should be used for the accurate calculation.

고콜레스테롤혈증 성인에서 울금과 명일엽 복합 추출물의 복용에 따른 혈중지질, 항산화 및 염증 관련 지표의 변화

윤선주,김미현,연지영,김명희,강명화,김태현,손연경 한국식품영양학회 2009 한국식품영양학회지 Vol.22 No.4

This study investigated the effects of Angelica keiskei Koidzumi and turmeric extract supplementation (ATE) on blood lipids, antioxidant and inflammatory markers in 35 hypercholesterolemic Korean adults with high blood cholesterol levels (serum total cholesterol≥200 ㎎/㎗ or LDL-cholesterol≥130 ㎎/㎗). They received ATE (n=21, 14 females and 7 males) or placebo (control group , n=14, 11 females and 3 males) for 4 weeks. There was no significant change in serum total cholesterol, LDL-cholesterol and HDL-cholesterol levels after ATE supplementation in the both groups. However, the LDL- cholesterol: HDL-cholesterol ratio (LPH) was significantly decreased and both serum prostagrandin E2 (PGE2) levels were significantly decreased in those receiving ATE. No significant changes were evident in interleukin (IL)-1β, IL-6, IL-8, 8-isoprostane, malondialehyde, total antioxidant capacity and oxidized-LDL. These results suggest that complex extract of Angelica keiske and Turmeric has the potential to decrease cardiovascular risk by reducing LPH and inflammatory mediator PGE2 in hypercholesterolemic adults. 고지혈증을 개선하고, 장기간 복용하더라도 독성이나 부작용 가능성을 낮출 수 있는 건강기능성 식품 소재의 발굴의 일환으로 항고지혈증 활성이 보고되고 있는 두 가지 천연소재 명일엽과 울금의 복합 추출물을 제조하여 고지혈증 치료지침 제정위원회의 지침에 따라 혈중 총 콜레스테롤 200 ㎎/㎗ 이상 또는 혈중 LDL-콜레스테롤 130 ㎎/㎗ 이상인 경계고지혈자와 고지혈자 총 35명을 대상으로 단일맹검법에 의해 일상적인 식이 섭취를 유지하도록 하면서 4주간 추출물 또는 위약을 복용하고 복용 전후의 혈중지질과 항산화 및 염증 지표의 변화를 관찰하였다. 실험군과 위약군의 총 콜레스테롤, LDL-콜레스테롤, HDL-콜레스테롤, 중성지질은 실험 전후에 유의적인 변화를 보이지 않았다. 그러나 실험군에서 LDL-콜레스테롤/HDL-콜레스테롤 비율은 명일엽과 울금 복합 추출물의 섭취 후 유의적으로 감소되었다(p<0.05). 염증지표인 PGE2는 실험군에서만 유의적인 감소를 보였고(p<0.05), IL-1β, IL-6, IL-8과 항산화지표인 MDA, TAC, oxidized-LDL은 두 군 모두에서 유의적인 변화를 보이지 않았다. 이상의 결과를 종합할 때 경계고지혈자와 고지혈자에서 명일엽과 울금 복합 추출물의 4주간 복용은 혈중 LDL-콜레스테롤/HDL-콜레스테롤의 비율과 염증지표인 PGE2의 유의적인 감소를 보여 고지혈증으로 인한 동맥 경화의 발생과 같은 심혈관 질환의 예방 가능성이 제시되었다. 그러나, 본 연구는 투여기간이 짧고, 추출물의 투여농도 또한 단일 수준이었으므로 고지혈증 예방과 관리를 위한 기능성 식품 개발 또는 식생활에의 적용을 위해서는 추가적인 연구가 필요하다고 생각된다.

LDL-콜레스테롤의 Friedewald 계산값과 실측값 비교

장성옥(Jang, Sungok),이종석(Lee, Jong-Seok) 한국산학기술학회 2015 한국산학기술학회논문지 Vol.16 No.8

LDL-콜레스테롤(LDL-C)은 심뇌혈관질환의 주된 교정 가능한 위험인자로서, 정확한 측정값을 임상에 적용하는 것이 중요하다. 하지만 LDL-C의 측정은 실제 측정이 아닌 Friedewald 공식에 의한 계산방법이 널리 이용되고 있다. 본 연구의 목적은 LDL-C의 Friedewald-추정값과 실측값을 비교하고, 두 방법의 LDL-C 위험수준 분류 일치도를 평가하는 것이다. 표본은 국민건강영양조사 2개년(2009년과 2010년)의 공개된 자료에서 추출되었고, 혈액 검사에서 총 콜레스테롤, HDL-콜레스테롤, 직접 측정한 LDL-C, 그리고 중성지방 중 어느 한 결측치도 없는 4,319명을 연구대상으로 하였다. 중성지방 400 mg/dL미만일 때, Friedewald-추정값과 실측값은 높은 상관관계를 보였고 (r = 0.958, p < 0.001), 위험수준 분류 일치 백분율은 82.7%이었다. 중성지방 수준이 높을수록, 일치 백분율은 낮았다. 중성지방 수준 150 mg/dL 미만, 150-200 mg/dL, 그리고 200-399 mg/dL일 때, 일치 백분율은 각각 85.4%, 78.2%, 그리고 71.4%이었다. Friedewald 공식은 중성지방 농도 150 mg/dL 미만에서는 LDL-C를 과대평가하는 반면, 중성지방 농도 150 mg/dL 이상에서는 과소평가하는 경향이 있었다. 이에 따라 LDL-C 위험수준 분류에 있어 그 범주가 과대평가된 사람은 382명 (9.1%)인 반면, 과소평가된 사람은 348명 (8.3%)이었다.이러한 결과는 Friedewald-추정값의 LDL-C 과소평가뿐만 아니라, 과대평가도 심각한 문제일 수 있음을 제시한다. Low-density lipoprotein cholesterol (LDL-C) is a major modifiable risk factor for cardio- cerebrovascular disease. In clinical practice, however, it is primarily calculated using the Friedewald formula as a cost-effective method. The aim of this study was to compare Friedewald-estimated and directly measured LDL-C values and assess the concordance in guideline LDL-C risk classification between the two methods. The data were derived from the 2009 and 2010 Korea National Health and Nutrition Survey (KNHANES). Analysis was done for 4,319 subjects with lipid panels―total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), directly measured LDL-C using an enzymatic homogeneous assay, and triglycerides (TG). For subjects with TG lower than 400 mg/dL, Friedewald-estimated and directly measured LDL-C were highly correlated (r = 0.958, p < 0.001) and overall concordance was 82.7%. As TG increased, overall concordance decreased. Overall concordance was 85.4% at TG lower than 150 mg/dL; 78.2% at TG of 150-199 mg/dL; and 71.4% at TG of 200-399 mg/dL. The Friedewld equation tended to overestimate LDL-C when TG are of < 150 mg/dL; however, underestimate LDL-C when TG are of ≥ 150 mg/dL. As a result, Friedewald estimation misclassified 382 subjects (9.1%) in a higher category versus 348 subjects (8.3%) in a lower category. Our findings suggest that overestimation of LDL-C by the Friedewald formula can be a great problem as well as underestimation.

Synthetic High-Density Lipoprotein-Like Nanocarrier Improved Cellular Transport of Lysosomal Cholesterol in Human Sterol Carrier Protein-Deficient Fibroblasts

남다은,김옥경,박유경,이정민 한국식품영양과학회 2016 Journal of medicinal food Vol.19 No.1

Sterol carrier protein-2 (SCP-2), which is not found in tissues of people with Zellweger syndrome, facilitates the movement of cholesterol within cells, resulting in abnormal accumulation of cholesterol in SCP-2-deficient cells. This study investigated whether synthetic high-density lipoprotein-like nanocarrier (sHDL-NC) improves the cellular transport of lysosomal cholesterol to plasma membrane in SCP-2-deficient fibroblasts. Human SCP-2-deficient fibroblasts were incubated with [3H-cholesterol]LDL as a source of cholesterol and sHDL-NC. The cells were fractionated by centrifugation permit tracking of [3H]-cholesterol from lysosome into plasma membrane. Furthermore, cellular content of cholesteryl ester as a storage form and mRNA expression of low-density lipoprotein (LDL) receptor were measured to support the cholesterol transport to plasma membrane. Incubation with sHDL-NC for 8 h significantly increased uptake of [3H]-cholesterol to lysosome by 53% and further enhanced the transport of [3H]-cholesterol to plasma membrane by 32%. Treatment with sHDLNC significantly reduced cellular content of cholesteryl ester and increased mRNA expression of LDL receptor (LDL-R). In conclusion, sHDL-NC enables increased transport of lysosomal cholesterol to plasma membrane. In addition, these data were indirectly supported by decreased cellular content of cholesteryl ester and increased gene expression of LDL-R. Therefore, sHDL-NC may be a useful vehicle for transporting cholesterol, which may help to prevent accumulation of cholesterol in SCP-2-deficient fibroblasts.

LDL-콜레스테롤의 추정: Friedewald 공식과 Martin 방법의 비교

장성옥,손희정,이종석 국가통계연구원 2015 통계연구 Vol.20 No.2

Low-density lipoprotein cholesterol (LDL-C) is a major risk factor for cardio-cerebrovascular disease such as myocardial infarction and stoke. While its accurate assessment is important, It is typically calculated using the Friedewald formula as a cost-effective method. In the Korea National Health Screening Program, LDL-C is calculated for subjects accounting for nearly 98% of its total participants when triglycerides are lower than 400 mg/dL. However, previous studies have suggested that the formula underestimates LDL-C, particularly at high triglyceride levels. In a recent study, the Martin Method as an alternative to the Friedewald formula was proposed to improve estimation of LDL-C. The aim of this study was to compare the performance of the Martin method and the Friedewald equation using a sample of 5,665 Korean adults with LDL-C measured by an enzymatic homogeneous assay (LDL-CD). The Friedewald LDL-C (LDL-CF) tended to underestimate LDL-C for subjects with triglycerides of ≥ 100 mg/dL and HDL-cholesterol levels of < 50 mg/dL. Based on the N strata of triglyceride and non-HDL- cholesterol and triglyceride levels, we generated the Martin LDL-C (LDL-CN) estimates including LDL-C5, LDL-C10, LDL-C20, LDL-C25, and LDL-C50. Compared with LDL-CF, each of LDL-CN estimates more closely approximated LDL-CD and exhibited a significantly higher overall concordance in the guideline risk classification with LDL-CD (p < 0.001 for each comparison). Overall concordance was 82.9% for LDL-CF, 85.5% for LDL-C5, and 85.8% for LDL-C25. The Martin method achieved the greatest improvement in concordance with LDL-CD at triglyceride levels of 200-399 mg/dL. In this triglyceride category, concordance was 70.4% for LDL-CF versus 80.0% for LDL-C5. Our findings suggest that the Martin method significantly improves LDL-C estimation when compared to the Friedewald formula. However, the new method requires validation in various populations to evaluate whether improvements over the Friedewald calculation are compelling enough to justify its adoption.

LDL 콜레스테롤 직접 측정법과 다양한 공식을 사용한 추정의 비교

권세영,나영악 대한임상검사과학회 2012 대한임상검사과학회지(KJCLS) Vol.44 No.3

Low-Density Lipoprotein cholesterol (LDLC) is the most important marker for the treatment of hyperlipidemia in NCEP-ATP III(National Cholesterol Education Program-Adult Treatment Panel III) guideline. Therefore, LDL cholesterol is pathologically meaningful, accurate measurement should be a top priority. Currently, LDLC is directly measured in most cases, but, the estimate is still used in mass health examination or screening test. This study is about the comparison of LDL-Cholesterol direct measurement with the estimate using various formula (Friedewald: [LDL-F=TC-HDL-TG/5], Nakajima: [LDL-N=TCHDL- TG/4], Hattori: [LDL-H =0.94TC -0.94HDL-0.19TG], Puavilai: [LDL-P=TC-HDL-TG/6], Carvalho: [LDL-C=3(TC-HDL)/4]) for calculating more accurate value. We analyzed total cholesterol (TC), tryglyceride (TG), high-density lipoprotein cholesterol (HDLC), and LDLC levels of 210 subjects between June and November in 2011. Until now, the Friedewald formula is the most commonly used estimate for the LDLC. When Friedewald formula was applied, the correlation coefficient (r) was 0.940, showing high correlation. But, the result of the direct method was significantly different, compared with those of the Friedewald formula in triglyceride levels≥400 mg/dL(p<0.05). There was the highest correlation when we used LDL-P formula(r=0.947) in triglyceride levels <400 mg/dl. Also there was the lowest mean difference regardless of triglyceride level. Therefore, the study showed that TG/6 is more precise means of calculation than TG/5. On the other hand, the calculation of LDL-Cholesterol was underestimated, compared with direct measurement. It is necessary to have more data and modified Friedewald formula should be used for the accurate calculation. .