esperable una buena corr<strong>el</strong>ación d<strong>el</strong> LDL con la fórmula <strong>de</strong>Frie<strong>de</strong>wald que <strong>para</strong> este rango <strong>de</strong> triglicéridos tiene unabuena concordancia.Mientras que <strong>para</strong> VLDL la corr<strong>el</strong>ación no es tanbuena, <strong>de</strong>bido a que se aparta, en un gran porcentaje <strong>de</strong> lapoblación estudiada, respecto d<strong>el</strong> valor Triglicéridos / 5asumido en la fórmula <strong>de</strong> Frie<strong>de</strong>wald.Se muestran a continuación los gráficos <strong>de</strong>corr<strong>el</strong>ación <strong>para</strong> <strong>las</strong> distintas lipoproteínas.Figura3. Corr<strong>el</strong>ación entre HDL por <strong>el</strong>ectroforesis y pormétodo tradicional.método <strong>el</strong>ectroforético aquí com<strong>para</strong>do reúne estascaracterísticas <strong>de</strong> exactitud y precisión.A<strong>de</strong>más, este método permite cuantificardirectamente <strong>el</strong> colesterol LDL y VLDL reemplazando <strong>el</strong>cálculo mediante la fórmula <strong>de</strong> Frie<strong>de</strong>wald, cuyo mayorerror resi<strong>de</strong> en asumir que la r<strong>el</strong>ación Triglicéridos /Colesterol en <strong>las</strong> VLDL es igual a 5, cuando en realida<strong>de</strong>ste valor es variable pudiendo ser muy diferente <strong>de</strong> 5 encasos patológicos.Por otro lado, este método <strong>el</strong>ectroforético permitedistinguir claramente <strong>el</strong> colesterol contenido en la Lp(a) d<strong>el</strong>contenido en la VLDL, permitiendo una cuantificaciónprecisa <strong>de</strong> la Lp(a), la cual es consi<strong>de</strong>rada un factor <strong>de</strong>riesgo in<strong>de</strong>pendiente <strong>de</strong> ateroclerosis. Se <strong>de</strong>be resaltar queun 23,2% <strong>de</strong> la población analizada presentaba Lp(a)<strong>el</strong>evada, a pesar <strong>de</strong> que sus niv<strong>el</strong>es <strong>de</strong> colesterol ytriglicéridos estaban en su rango normal.Figura 4. Corr<strong>el</strong>ación entre LDL por <strong>el</strong>ectroforesis y pormétodo tradicional.Figura 5. Corr<strong>el</strong>ación entre VLDL por <strong>el</strong>ectroforesis y pormétodo tradicional.3. ConclusionesPara c<strong>las</strong>ificar a los pacientes en cuanto a riesgo<strong>de</strong> evento cardiovascular o <strong>para</strong> evaluar la eficacia <strong>de</strong>tratamientos <strong>de</strong> reducción <strong>de</strong> lípidos se requiere unacuantificación exacta y precisa <strong>de</strong> <strong>las</strong> lipoproteínas. ElREFERENCIAS1. Sacks FM, Pfeffer MA, Moye LA, Rouleau JL,Rutherford JD, Cole TG, et al. The effect ofpravastatin on coronary events after myocardialinfarction in patients with average cholesterollev<strong>el</strong>s. Cholesterol and Recurrent Events Trialinvestigators. N Engl J Med 335, 1001–9, 1996.2. Executive summary of the third report of theNational Cholesterol Education Program (NCEP)Expert Pan<strong>el</strong> on Detection, Evaluation, andTreatment of High Blood Cholesterol in Adults(Adult Treatment Pan<strong>el</strong> III). JAMA 285, 2486–97,2001.3. Cast<strong>el</strong>li WP, Garrison RJ, Wilson PW, Abbott RD,Kalousdian S, Kamm<strong>el</strong> WB. Inci<strong>de</strong>nce of coronaryheart disease and lipoprotein lev<strong>el</strong>s: theFramingham study. JAMA 256, 2835–8, 1986.4. Bachorik PS, Ross JW. National CholesterolEducation Program recommendations formeasurements of low-<strong>de</strong>nsity lipoproteincholesterol: executive summary. NationalCholesterol Education Program Working Group onLipoprotein Measurements. Clin Chem 41, 1414–20, 1995.5. Myers GL, Cooper GR, Hen<strong>de</strong>rson LO, HassemerDJ, Kimberly MM. Standardization of lipid andlipoprotein measurement. In: Rifai N, Warnick GR,Domoniczak MH, eds. Handbook of lipoproteintesting. Washington: AACC Press, 717–48, 2000.6. Cooper GR, Smith SJ, Duncan IW, Mather A,F<strong>el</strong>lows WD, Foley T, et al. Interlaboratory testingof the transferability of a candidate referencemethod for total cholesterol in serum. Clin Chem32, 921–9, 1986.7. Myers Myers GL, Kimberly MM, Waymack PP,Smith SJ, Cooper GR, Sampson EJ. A referencemethod laboratory network for cholesterol: a mod<strong>el</strong>for standardization and improvement of clinicalEne – Feb 2008 23
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