Evaluation Of The Effect Of Triglyceride Concentrations On Direct Ldl Cholesterol Levels

Yıl 2016, Cilt: 8 Sayı: 3, 107 - 114, 27.11.2016

Kübranur Ünal

Öz

Objectives: Non-HDL cholesterol has been accepted as an alternative marker to LDL cholesterol in patients with high triglyceride levels in recent years. In this study, we aimed to investigate the effect of triglyceride concentrations on direct LDL-C determination method in comparison with non-HDL-C cholesterol used as an independent variable.

Materials and Methods: Samples were collected from patients who admitted to Ankara Numune Training and Research Hospital Biochemistry Laboratory for analysis of lipid profile during January-June 2012. The results were categorized as 7 groups according to triglyceride levels. 1. Group 0-200 mg / dl (n = 28, 56.2 + 11.8 years), 2 Group 200-400 mg / dl (n = 30, 54.2 ± 10.7 years), 3. Group 400-450 mg /dl (n = 52, 55.7 ± 10.9 years), 4.Group 450 -500 mg / dl (n = 27, 55.5 ± 10.6 years); 5.Group 500-600 mg / dl (n = 25, 56.5 ±11.3 years); 6.Group 600-700 mg / dl (n = 26, 56.8 ± 11.8 years); 7.Group >700 mg / dl (n = 34, 56.6 ± 11.1 years), respectively. Friedewald calculation and direct measurement of LDL-C levels were performed according to trygliceride levels.
Results: Correlation of each group between direct LDL-C and non-HDL-C; 1,Group (p < 0.001, r = 0.928), 2. Group (p < 0.001, r: 0.935 :); 3. Group (p < 0.001, r =0.925); 4. Group (p < 0.001, r = 0.865); 5.Group (p < 0.001, r = 0.895); 6.Group (p < 0.001, r = 0.835), 7.Group (p = 0 , 117, r:-0,251), respectively.

Conclusion: LDL-C concentrations can not be calculated using Friedewald formula when TG concentrations are higher than 400 mg/dL. In this situation LDL-C levels are determined using direct LDL-C method. In our study, a lack of correlation between non-HDL-C and direct LDL-C tests has been observed as TG levels rise and after TG concentrations exceeded 700 mg/dL, direct LDL-C levels were thought to be interfered.lt is concluded that, detailed clinical studies are needed to explore the effectiveness of non-HDL-C test, which has been accepted as an alternative to LDL-C test for patients with high TG levels.

Anahtar Kelimeler

Non-HDL-K, LDL-K, ateroskleroz, Non-HDL-C, LDL-C, atherosclerosis

Trigliserit Konsantrasyonlarının Direkt Ldl Kolesterol Düzeylerine Etkisinin Değerlendirilmesi

Öz

Amaç: Non-HDL kolesterol yüksek trigliserit konsantrasyonuna sahip bireylerde alternatif bir belirteç olarak kabul edilmiştir. Direkt LDL-K ölçümünün yüksek TG konsantrasyonlarında yöntemsel olarak etkilendiği düşünülmektedir. Bu çalışmada, non-HDL-K düzeyleri dayanak alınarak, direkt LDL-K yönteminin hangi TG değerlerinden sonra belirgin olarak etkilendiğini değerlendirmeyi amaçladık.

Materyal ve Metot: Ocak-Haziran 2012 tarihleri arasında Ankara Numune Eğitim ve Araştırma Hastanesi Merkez Biyokimya laboratuarına lipit analizi için gönderilen hasta numuneleri trigliserit düzeyine göre 7 gruba ayrıldı: 1. Grup 0-200 mg/dl (n = 28, yaş 56,2±11,8), 2. Grup 200-400 mg/dl (n= 30, yaş 54,2±10,7), 3.Grup 400-450 mg/dl (n = 52, yaş 55,7±10,9), 4.Grup 450-500 mg/dl (n = 27 , yaş 55,5±10,6); 5.Grup 500-600 mg/dl (n = 25 yaş 56,5±11,3); 6.Grup 600-700 mg/dl (n = 26 , yaş 56,8±11,8); 7.Grup >700 mg/dl (n = 34 , yaş 56,6±11,1)idi. Tüm numunelerde LDL-K analizi, Friedewald yöntemi ile hesaplandı ve direkt LDL-K kiti ile ölçüldü.

Bulgular: Her bir grupta direkt LDL-K ve non-HDL-K arasındaki korelasyon; 1 .Grup (p < 0,001, r: 0,928), 2.Grup (p < 0,001, r: 0,935:); 3.Grup (p < 0,001, r: 0,925); 4. Grup (p < 0,001, r: 0,865); 5.Grup(p < 0,001, r: 0,895); 6.Grup (p < 0,001, r: 0,850) ; 7.Grup (p = 0,117, r:-0,249) idi.
Sonuç: TG düzeylerinin 400 mg/dL nin üzerinde olduğu durumlarda Fridewald formülü ile LDL-K düzeyleri rapor edilememekte, LDL-K düzeyleri direkt LDL-K yöntemi ile çalışılmaktadır. Çalışmamızda TG düzeyleri yükseldikçe direkt LDL-K yönteminin de etkilendiği ve non-HDL-K ile korelasyonunun kaybolduğu gözlenmiştir. Bu durum, TG konsantrasyonu > 700 mg/dl bulunan bireylerde direkt LDL-K yönteminin de TG konsantrasyonundan ileri derecede etkilendiği şeklinde yorumlanmıştır. TG düzeyleri yüksek olan hastaların takibinde direkt LDL-K’ye alternatif olarak sunulan non-HDL-K testi ile ilgili kapsamlı klinik çalışmaların yapılması gerektiği düşünülmektedir.

Kübranur ÜNAL
Sevilay SEZER
Fatma Meriç YILMAZ
Nihal BOĞDAYCIOĞLU

Anahtar Kelimeler

Non-HDL-K, LDL-K, ateroskleroz

Kaynakça

• 1. Executive Summary of the Third Report of the National Cholesterol Education Program (NCEP). Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult TreatmentPanellll).JAMA2001;285:248 6-97.
• 2. Ravi GR, Pradeepa R, Mohan V. Hypertriglyceridemia and coronary artery disease-an update. Indian Heart J 2004;56:21-6.
• 3. Assmann G, Schulte H, Von Eckards-tein A. Hypertriglyceridemia and elevated lipoprotein(a) are risk factors for major coronary events in middle-aged men. Am J Cardiol 1996;77:1179-84.
• 4. Austin MA, Hokanson JE, Edwards KL. Hypertriglyceridemia as a cardiovascular risk factor. Am J Cardiol 1998; 81:7-12.
• 5. Grundy SM. Hypertriglyceridemia, atherogenic dyslipidemia, and the metabolic syndrome. Am J Cardiol 1998;81:18-25.
• 6. Sacks FM, Alaupovic P, Moye LA, et al. VLDL, Apolipoproteins B, Clll, and E, and Risk of Recurrent Coronary Events in the Cholesterol and Recurrent Events (CARE) Trial. Circulation 2000;102: 1886-92.
• 7. Wu T, Willett WC, Rifai N, et al. Is plasma oxidized low-density lipoprotein, measured with the widely used antibody 4E6, an independent predictor of coronary heart disease among U.S. men and women? J Am Coll Cardiol 2006;48: 973-79.
• 8. Friedewald WT, Levy RI, Fredrickson DS. Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge. Clinical Chemistry 1972;18:499-502.
• 9. Mora S, Rifai N, Buring JE, Ridker PM. Comparison of LDL cholesterol concentrations by Friedewald calculation and direct measurement in relation to cardiovascular events in 27 331 women. Clinical Chemistry 2009;55:888-94.
• 10. Choi SY, Park HE, Kim MK. Difference between calculated and direct-measured low-density lipoprotein cholesterol in subjects with diabetes mellitus or taking lipid-lowering medications. Journal of Clinical Lipidology 2012;6:114-20.
• 11. Wu T, Willett WC, Rifai N, et al. Is plasma oxidized low-density lipoprotein, measured with the widely used antibody 4E6, an independent predictor of coronary heart disease among U.S. men and women? J Am Coll Cardiol 2006;48: 973-79.
• 12. Liu J, Sempos C, Donahue RP, et al. Joint distribution of non-HDL and LDL cholesterol and coronary heart disease risk prediction among individuals with and without diabetes. Diabetes Care 2005;28:1916-21.
• 13. Sniderman A, McQueen M, Contois J, Williams K, Furberg CD. Why is non-high-density lipoprotein cholesterol a better marker of the risk of vascular disease than low-density lipoprotein cholesterol? J Clin Lipidol 2010;4:152-55.
• 14. Burillo E, Andres EM, Mateo-Gallego R, et al. High-density lipoprotein cholesterol increase and non-cardiovascular mortality: a meta-analysis. Heart 2010; 96:1345-51.
• 15. Brunzell JD, Davidson M, Furberg CD, et al. Lipoprotein management in patients with cardiometabolic risk: consensus conference report from the American Diabetes Association and the American College of Cardiology Foundation. J Am Coll Cardiol 2008;51: 1512-24.
• 16. Blaha M, Blumenthal R, Brinton E, Jacobson TA. National Lipid Association Taskforce on Non-HDL Cholesterol. The importance of non-HDL cholesterol reporting in lipid management. J Clin Lipidol 2008;2:267-73.
• 17. Srinivasan SR, Myers L, Berenson GS. Distribution and correlates of non-high-density lipoprotein cholesterol in children: The Bogalusa Heart Study. Pediatrics 2002;110:29.
• 18. Vega GL, Grundy SM. Does measurement of apolipoprotein B have a place in cholesterol management. Arteriosclerosis 1990;10:668-71.
• 19. Abate N, Vega GL, Grundy SM. Variability in cholesterol content and physical properties of lipoproteins containing apolipoprotein B-100. Atherosclerosis 1993;104:159-71.
• 20. Executive summary of the third report of the National Cholesterol Education Program(NCEP) Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA 2001 ;285: 2486-97.
• 21. Me Gill HC. The Pathogenesis of Atherosclerosis. Clin Chern 1988;34:33-9.
• 22. Steinberg D. Atherogenesis in perspective: Hypercholesterolemia and inflammation as partners in crime. Nature Medicine 2002;8:1211-17.
• 23. Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Executive summary of the third report of the national cholesterol education program (NCEP) expert panel on detection, evaluation, and treatment of high blood cholesterol in adults (Adult Treatment Panel III). JAMA 2001 ;285: 2486- 97.
• 24. Executive summary of the third report of the National Cholesterol Education Program(NCEP) Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). JAMA 2001 ;285: 2486-97.
• 25. Smets EML, Pequeriaux NCV, Blaton V, Goldschmidt HMJ. Analytical Performance of a Direct Assay for LDL-Cho-lesterol. Clin Chern Lab Med 2001 ;39: 270-80.
• 26. Nauck M, Warnick GR, Rifai N. Methods for Measurement of LDL-Cholesterol: A Critical Assessment of Direct Measure-merit by Homogeneous Assays versus Calculation. Clin Chern 2002;48:236-54.
• 27. Friedewald WT, Levy RI, Frederickson DS. Estimation of the Concentration of Low- Density Lipoprotein Cholesterol in Plasma, Without Use of the Preparative Ultracentrifuge, Clin Chern, 1972; 18: 499-502.
• 28. Nauck M, Graziani MS, Bruton D, et al. Analytical and Clinical Performance of a Detergent-based Homogeneous LDL-Cholesterol Assay: A Multicenter Evaluation. Clin Chern 2000;46:506-14.
• 29. Esteban-Salan M, Guimon-Bardesi A, De La Vuida-Unzueta J, et al. Analytical and Clinical Evaluation of Two Homogenous Assays for LDL-cholesterol in Hyperlipidemic Patients. Clin Chern 2000;46:1121-31.
• 30. Rifai N, Bachorik PS, Albers JJ. Lipids, lipoproteins and apolipoproteins. In: Burtis CA, Ashwood ER; eds. Tietz Textbook of Clinical Chemistry. 3rd ed. Philadelphia: WB. Saunders Company; 1999:809-61.
• 31. Frost PH, Havel RJ. Rational use of non-high-density lipoprotein cholesterol screening and assessment of risk and therapy. Am J Cardiol 1998;81:26B-31B.