Observational study of lipid profile and LDL particle size in patients with metabolic syndrome.

BACKGROUND: The atherogenic lipoprotein phenotype is characterized by an increase in plasma triglycerides, a decrease in high-density lipoprotein cholesterol (HDLc), and the prevalence of small, dense-low density lipoprotein cholesterol (LDLc) particles. The aim of this study was to establish the importance of LDL particle size measurement by gender in a group of patients with Metabolic Syndrome (MS) attending at a Cardiovascular Risk Unit in Primary Care and their classification into phenotypes. SUBJECTS AND METHODS: One hundred eighty-five patients (93 men and 92 women) from several areas in the South of Spain, for a period of one year in a health centre were studied. Laboratory parameters included plasma lipids, lipoproteins, low-density lipoprotein size and several atherogenic rates were determinated. RESULTS: We found differences by gender between anthropometric parameters, blood pressure and glucose measures by MS status. Lipid profile was different in our two study groups, and gender differences in these parameters within each group were also remarkable, in HDLc and Apo A-I values. According to LDL particle size, we found males had smaller size than females, and patients with MS had also smaller than those without MS. We observed inverse relationship between LDL particle size and triglycerides in patients with and without MS, and the same relationship between all atherogenic rates in non-MS patients. When we considered our population in two classes of phenotypes, lipid profile was worse in phenotype B. CONCLUSION: In conclusion, we consider worthy the measurement of LDL particle size due to its relationship with lipid profile and cardiovascular risk.

Evaluación de un método electroforético para el subfraccionamiento de las partículas plasmáticas de lipoproteínas de baja densidad / Evaluation of an electrophoresis method to obtain plasma low density lipoproteins subfractions

Desde que el NCEP ATP III (National Cholesterol Education Program. Adult Treatment Panel III) aceptó el predominio de partículas LDL (low density lipoproteins "lipoproteínas de baja densidad") pequeñas y densas como factor de riesgo emergente de desarrollo de enfermedad cardiovascular, el interés por los métodos para fraccionar las LDL ha aumentado. Por eso, el presente trabajo pretende valorar la utilidad de un sistema de electroforesis en gel de poliacrilamida (Lipoprint(R)) para separar LDL en nuestra población. Se recogieron 194 muestras de sangre de personas de entre 15 y 94 años (el 49%, hombres) y se calculó la imprecisión del ensayo, así como los valores de referencia por sexo. Además, se realizaron correlaciones entre los distintos parámetros lipídicos. Se obtuvieron resultados aceptables para el estudio de imprecisión mediante el sistema Lipoprint®. Al correlacionar el diámetro medio de las partículas LDL con otros marcadores del metabolismo lipídico, destacamos una asociación inversamente proporcional con la concentración de triglicéridos y apolipoproteína (apo) B100 y directamente proporcional con la de colesterol ligado a lipoproteínas de alta densidad (cHDL). Encontramos diferencias entre sexos en los niveles de triglicéridos y colesterol ligado a LDL (mayores en hombres), y cHDL y diámetro medio de las partículas LDL (mayores en mujeres). Al comparar el diámetro medio de las partículas LDL con los parámetros lipídicos encontramos que está asociado inversamente con la concentración de triglicéridos y apo B100, y directamente con la de cHDL, lo que se asocia a un mayor riesgo cardiovascular. El sistema Lipoprint® es útil para la medida de la concentración y diámetro medio de las partículas LDL debido a su sencillez y rapidez de resultados. Aún así faltan estudios que relacionen los resultados obtenidos con los parámetros clínicos que se emplean en la valoración del riesgo cardiovascular (AU)

Since NCEP ATP III accepted the small and dense LDL particle as an emergent risk factor of cardiovascular disease, the methods to calculate LDL subfractions have increased. The present report attempts to evaluate the usefulness of a polyacrylamide gel electrophoresis system (LipoprintTM) to separate LDL in our population. 194 blood samples were collected from subjects between 15–94 years old (49% men). Imprecision and lipid parameter study population ranges by sex, and the correlations between them were calculated. Imprecision study results were acceptable. When correlating the average diameter of particle LDL with other lipid markers, we observed an inverse association with triglyceride concentration and Apo B100, and a direct association with HDL-cholesterol. We found differences between sex in triglyceride and LDL-cholesterol levels (greater in men) and HDL-cholesterol and average diameter of LDL particles (greater in women). When comparing the average LDL particle diameter with the lipid parameters, we found that it is inversely associated with the triglyceride and Apo B100 concentration, and directly with HDL-cholesterol, which is associated with a greater cardiovascular risk. We believe that LipoprintTM system is useful for the measurement of the concentration and average diameter of LDL particles, due to its simplicity and speed of results. Nevertheless, studies are needed that can associate the results obtained to the clinical parameters that are used in the evaluation of cardiovascular risk (AU)

[LDL concentration and particle size after treatment with rosiglitazone in patients with diabetes mellitus type 2]. / Concentración y tamaño de las partículas de LDL tras el tratamiento con rosiglitazona en pacientes con diabetes mellitus tipo 2.

BACKGROUND AND OBJECTIVE: The effects of rosiglitazone on the lipid profile are controversial, with related increases in the concentration of total and LDL cholesterol. Our objective is to evaluate the evolution of the concentration and size of LDL particles in a group of patients with type 2 diabetes mellitus taking rosiglitazone. PATIENTS AND METHODS: We studied 30 patients under treatment with oral antidiabetics to whom rosiglitazone was added to their initial therapy. The following tests were determined before and after 6 months of treatment: glucose, total cholesterol, HDL, LDL, triglycerides, C reactive protein, lipoprotein (a) and glycosylated haemoglobin. The average diameter of the particles LDL was also estimated, as well as the probability of cardiovascular events up to ten years, according to the Framingham and SCORE model. RESULTS: Statistically significant reductions of glucose, HbA(1C) and CRP levels, and an increase of total cholesterol, cholesterol LDL and triglycerides concentrations were observed, with statistical significance for total cholesterol. A significant increase in the estimation of cardiovascular risk up to ten years was found. No modifications either in the concentrations of HDL-c and Lp (a) or in the average size of LDL particles were detected. CONCLUSIONS: After treatment with rosiglitazone, there is an increase of total cholesterol concentrations without variation in the mean size of LDL particles. Nevertheless, the reduction of CRP, and thus of inflammation is clear, with prevention of the progression of atherosclerosis.

Concentración y tamaño de las partículas de LDL tras el tratamiento con rosiglitazona en pacientes con diabetes mellitus tipo 2 / LDL concentration and particle size after treatment with rosiglitazone in patients with diabetes mellitus type 2

Fundamento y objetivo: los efectos de la rosiglitazona en el perfil lipídico son controvertidos, y se han descrito aumentos en la concentración de colesterol total y del colesterol unido a lipoproteínas de baja densidad (LDL). Nuestro objetivo es evaluar la concentración y el tamaño de las partículas de LDL en un grupo de pacientes con diabetes mellitus tipo 2, a los que se les añadió rosiglitazona a su tratamiento inicial. Pacientes y método: se estudió a 30 pacientes diagnosticados de diabetes mellitus tipo 2 en tratamiento con antidiabéticos orales. Se determinaron las pruebas siguientes, antes y tras 6 meses de tratamiento con rosiglitazona añadida a su tratamiento inicial: glucosa, colesterol total, colesterol unido a lipoproteínas de alta densidad (HDL), colesterol LDL (cLDL), triglicéridos, proteína C reactiva (PCR), lipoproteína (a) y hemoglobina glucosilada (HbA1C). Además, se estimó el diámetro medio de las partículas LDL y se calculó la probabilidad de episodios cardiovasculares a 10 años según el modelo Framingham y SCORE. Resultados: encontramos una reducción estadísticamente significativa de los valores de glucosa, HbA1C y PCR, y un aumento de las concentraciones de colesterol total, cLDL y triglicéridos, con significación estadística para el colesterol total. Observamos un incremento significativo en la estimación del riesgo cardiovascular a 10 años. No encontramos variaciones en las concentraciones de colesterol HDL, lipoproteína (a) ni tampoco en el diámetro medio de las partículas LDL. Conclusiones: tras el tratamiento con rosiglitazona hay un aumento de la concentración de colesterol total, sin variación en el tamaño medio de la partícula LDL. Sin embargo, es clara la reducción de la PCR y, con ella, de la inflamación, que previene la progresión de la aterosclerosis (AU)

Background and objective: The effects of rosiglitazone on the lipid profile are controversial, with related increases in the concentration of total and LDL cholesterol. Our objective is to evaluate the evolution of the concentration and size of LDL particles in a group of patients with type 2 diabetes mellitus taking rosiglitazone. Patients and methods: We studied 30 patients under treatment with oral antidiabetics to whom rosiglitazone was added to their initial therapy. The following tests were determined before and after 6 months of treatment: glucose, total cholesterol, HDL, LDL, triglycerides, C reactive protein, lipoprotein (a) and glycosylated haemoglobin. The average diameter of the particles LDL was also estimated, as well as the probability of cardiovascular events up to ten years, according to the Framingham and SCORE model. Results: Statistically significant reductions of glucose, HbA1C and CRP levels, and an increase of total cholesterol, cholesterol LDL and triglycerides concentrations were observed, with statistical significance for total cholesterol. A significant increase in the estimation of cardiovascular risk up to ten years was found. No modifications either in the concentrations of HDL-c and Lp (a) or in the average size of LDL particles were detected. Conclusions: After treatment with rosiglitazone, there is an increase of total cholesterol concentrations without variation in the mean size of LDL particles. Nevertheless, the reduction of CRP, and thus of inflammation is clear, with prevention of the progression of atherosclerosis (AU)