Activity of Lipoprotein-Associated Enzymes in Indigenous Children Living at Different Altitudes.

BACKGROUND: High altitude is associated with hypobaric hypoxia, and metabolic modifications. In particular, alterations to lipoprotein-associated enzymes have been reported under hypoxia. OBJECTIVE: To determine the association between paraoxonase 1 (PON-1) and Cholesteryl-ester transfer protein (CETP) activities and altitude in two groups of Argentinean Indigenous schoolchildren living at different altitudes. METHODS: A cross-sectional study compared 151 schoolchildren from San Antonio de los Cobres (SAC), 3,750 m, with 175 schoolchildren from Chicoana (CH), 1,400 m. Anthropometric data, lipids, apolipoprotein (apo) A-I, apo B, plus PON-1 and CETP activities were determined. RESULTS: The prevalence of overweight/obesity was significantly lower in SAC than in CH. Z- BMI (0.3 vs 0.7), Apo A-I/Apo B (1.67 vs. 1.85) and PON-1 (170 vs. 243 nmol/mL.min) were significantly lower in SAC than in CH, respectively. Total cholesterol (156 vs 144 mg/dL), triglycerides (TG) (119 vs. 94 mg/dL), apo A-I (133 vs. 128 mg/dL), apo B (84 vs. 73 mg/dL), hematocrit (48 vs. 41%), transferrin (295 vs. 260 mg/dL) and CETP (181 vs. 150%/mL.h) were significantly higher in SAC than in CH. There was a significant univariate association between altitude and transferrin (r0.38), hematocrit (r0.75), TG (r0.24), apo B (r0.29), PON-1 (r-0.40), and CETP (r0.37). Multiple linear regression analyses showed that altitude was significantly associated with children's TG (ß = 0.28, R2 = 0.14), HDL-C (ß = â€’0.27; R2 = 0.23), apo B (ß = 0.32; R2 = 0.14), CETP (ß = 0.38; R2 = 0.15) and PON-1 (ß = â€’0.36; R2 = 0.16), adjusted for age, gender and BMI. CONCLUSION: SAC children presented a more atherogenic lipid profile, plus lower PON1 and higher CETP activities, than CH children.

Lipid transfers to HDL are diminished in long-term bedridden patients: association with low HDL-cholesterol and increased inflammatory markers.

Plasma lipids have been extensively studied in sedentary and in subjects practicing exercise training, but not in extreme inactivity as occurs in bedridden patients. This is important for the care of bedridden patients and understanding the overall plasma lipid regulation. Here, we investigated plasma lipids, lipid transfers to HDL and inflammatory markers in bedridden patients. Fasting blood samples were collected from 23 clinically stable bedridden patients under long-term care (>90 days) and 26 normolipidemic sedentary subjects, paired for age and gender. In vitro transfer of four lipids to HDL was performed by incubating plasma with donor nanoparticles containing radioactive lipids. Total (193 ± 36 vs 160 ± 43, p = 0.005), LDL (124 ± 3 vs 96 ± 33 p = 0.003) and HDL-cholesterol (45 ± 10 vs 36 ± 13, p = 0.008), apolipoprotein A-I (134 ± 20 vs 111 ± 24, p = 0.001) and oxidized LDL (53 ± 13 vs 43 ± 12, p = 0.011) were lower in bedridden patients, whereas triglycerides, apolipoprotein B, CETP and LCAT were equal in both groups. Transfers of all lipids, namely unesterified cholesterol, cholesterol esters, triglycerides and phospholipids, to HDL were lower in bedridden patients, probably due to their lower HDL-cholesterol levels. Concentrations of IL-1ß, IL-6, IL-8, HGF and NGF were higher in bedridden patients compared to sedentary subjects. In conclusion, inactivity had great impact on HDL, by lowering HDL-cholesterol, apolipoprotein A-I and thereby cholesterol transfers to the lipoprotein, which suggests that inactivity may deteriorate HDL protection beyond the ordinary sedentary condition.

[Protective role of high density lipoproteins in sepsis: basic issues and clinical implications]. / Papel protector de las lipoproteínas de alta densidad en sepsis: aspectos básicos e implicancias clínicas.

High density lipoproteins (HDL) are responsible of reverse cholesterol transport and play an important antiatherogenic role. In recent years, several studies suggest that HDL have additional functions, including a possible anti-inflammatory activity in infectious conditions. Furthermore, available evidence indicates that the presence of lipopolysaccharide (LPS) within the circulation during infectious states induced by gram-negative bacteria may be involved in the decrease in HDL cholesterol levels and changes in lipoprotein composition, which have been associated with a higher mortality due to sepsis in animal models and in humans. In this article, we review this subject and also discuss possible mechanisms that explain the positive impact achieved by native HDL, reconstituted HDL, or HDL apolipoprotein peptides on the inflammatory response and mortality in models of endotoxemia. In this regard, it has been proposed that one of the mechanisms by which HDL protect against sepsis may be mediated by its binding ability and/or neutralizing capacity on LPS, avoiding an excessive response of the immune system. Thus, increasing blood levels of HDL and/or parenteral HDL administration may represent a new anti-inflammatory tool for managing septic states in humans.

Papel protector de las lipoproteínas de alta densidad en sepsis: aspectos básicos e implicancias clínicas / Protective role of high density lipoproteins in sepsis: basic issues and clinical implications

High density lipoproteins (HDL) are responsible of reverse cholesterol transport and play an important antiatherogenic role. In recent years, several studies suggest that HDL have additional functions, including a possible anti-inflammatory activity in infectious conditions. Furthermore, available evidence indicates that the presence of lipopolysaccharide (LPS) within the circulation during infectious states induced by gram-negative bacteria may be involved in the decrease in HDL cholesterol levels and changes in lipoprotein composition, which have been associated with a higher mortality due to sepsis in animal models and in humans. In this article, we review this subject and also discuss possible mechanisms that explain the positive impact achieved by native HDL, reconstituted HDL, or HDL apolipoprotein peptides on the inflammatory response and mortality in models of endotoxemia. In this regard, it has been proposed that one of the mechanisms by which HDL protect against sepsis may be mediated by its binding ability and/or neutralizing capacity on LPS, avoiding an excessive response of the immune system. Thus, increasing blood levels of HDL and/or parenteral HDL administration may represent a new anti-inflammatory tool for managing septic states in humans.

Las lipoproteínas de alta densidad (HDL) son responsables del transporte reverso de colesterol y ejercen un importante papel anti-aterogénico. En los últimos años, diversos estudios indican que las HDL también tendrían otras funciones críticas, incluyendo una posible actividad anti-inflamatoria durante estados infecciosos. Además, la evidencia disponible sugiere que la presencia de lipopolisacárido (LPS) en la circulación durante estados infecciosos inducidos por bacterias gramnegativas podría estar involucrado en la disminución del colesterol HDL y los cambios en composición de esta clase lipoproteínas, lo cual se asociaría con una mayor tasa de mortalidad por sepsis en modelos animales y en humanos. En este trabajo, se revisan los antecedentes mencionados y además se discuten posibles mecanismos que explican la disminución de la respuesta inflamatoria y de la mortalidad que se logran en modelos de endotoxemia tratados con HDL o preparaciones similares. En este sentido, se ha propuesto que uno de los mecanismos protectores de las HDL estaría mediado por su capacidad de unión y/o neutralización del LPS, evitando una respuesta exacerbada del sistema inmune. De esta manera, el aumento de los niveles sanguíneos de HDL y/o su administración parenteral podrían constituir nuevas herramientas anti-inflamatorias para el manejo de estados sépticos en humanos.

Variabilidade interensaios de dislipidemias em pacientes hipertensos / Inter-assays variability of dislipidemias in hypertensive patients

INTRODUÇÃO E OBJETIVOS: Ensaios de diferentes procedências para avaliação das dislipidemia podem resultar em variações significativas nos resultados obtidos e consequente conduta inadequada pelo clínico. O estudo objetivou comparar resultados laboratoriais de colesterol total (CT), triglicérides (TG), colesterol da lipoproteína de alta densidade (HDL-C), colesterol da lipoproteína de baixa densidade (LDL-C), apolipoproteína A-1 (Apo A-1), apolipoproteína B (Apo B) e lipoproteína (a) (Lp[a]) e índices lipídicos (não-HDL-C, CT/HDL-C, LDL-C/HDL-C, TG/HDL-C e Apo B/HDL-C) de pacientes hipertensos e/ou diabéticos diagnosticados. MÉTODOS: Foram utilizados conjuntos reativos, e os respectivos analisadores Gold Analisa, Dia Sys (CCX - Abbott), Dade Behring (Nefelômetro BN 100) e Roche (COBAS Integra 400), para verificar a reprodutibilidade dos resultados obtidos. Participaram 99 pacientes (36 do sexo masculino e 63 do feminino). Comparando os resultados, verificamos que: todas as médias obtidas dos constituintes lipídicos apresentaram diferença significativa; número semelhante de pacientes apresentou níveis séricos elevados de CT, TG, Lp(a) e Apo A-1. O HDL-C, o LDL-C e a Apo B apresentaram discordância, assim como os índices de CT/LDL-C, LDL-C/HDL-C e TG/HDL-C. Para não-HDL-C e ApoB/HDL, houve semelhança no número de pacientes com valores não recomendados. Em consequência da diferença, em relação ao LDL-C, a decisão da conduta terapêutica poderá ser inadequada, enquanto o não-HDL-C, além de evidenciar partículas aterogênicas, apresentou número de hipertensos com valores séricos não referendados semelhantes, independente da metodologia e do equipamento utilizado. CONCLUSÃO: No grupo de hipertensos analisados, o não-HDL-C se caracterizou um importante fator de correção interensaios de parâmetros lipídicos. E sua associação à relação Apo B/HDL-C pode ser um fator adicional em relação às condutas hipolipemiantes a serem adotadas.

INTRODUCTION AND OBJECTIVES: Different assays to evaluate dyslipidemia may show significant variations in the obtained results and a consequent inappropriate clinical approach may be adopted. This study aimed to compare the results of total cholesterol (CT), triglycerides (TG), HDL-C, Apo A1, Apo B, lipoprotein (a) and lipidic indexes (not-HDL-C, CT/HDL-C, LDL-C/HDL-C, TG/HDL-C and Apo B/HDL-C) of hypertensive and/or diabetic patients. METHODS: The following reactive kits and respective analyzers were applied to verify the reproducibility of results: Gold Analisa, DiaSys (CCX-ABBOTT), Dade Behring (Nephelometer BN 100) and Roche (COBAS Integra 400). Ninety nine patients (36 male and 63 female gender) were investigated. Comparing the results, we observed that all mean numbers of lipid constituents showed a significant difference. A similar number of patients had high CT, TG, Lp (a) and Apo A-1 serum levels. There was also disagreement in HDL-C, LDL-C, ApoB, CT/LDL-C, LDL-C/HDL-C and TG/HDL-C indexes. For not-HDL-C and ApoB/HDL, there was similarity in the number of patients with not recommended values. As a consequence of this difference, the choice of therapeutic approach may be inappropriate as to LDL-C levels, whereas Not-HDL-C not only showed atherogenic particles but also a number of hypertensive patients with similar not recommended serum values, regardless of the methodology and the equipment used. CONCLUSION: In the analyzed group of hypertensive patients, not-HDL-C was an important inter assay correction factor of lipidic parameters. The association with Apo B/HDL-C relation may be an additional factor as to the choice of hypolipemiant treatments.

Perspectivas futuras / Future perspectives

A terapêutica das dislipidemias tem se voltado para a redução dos níveis de LDL-colesterol, por inibir a síntese endógena do colesterol ou por bloquear sua absorção, conseguindo-se, assim, maior alcance de metas, com fármacos cada vez mais potentes, especialmente quando usados em associação. Fibratos e ácido nicotínico, agindo preferencilamente sobre os triglicérides, promovem maiores aumentos de HDL-colesterol e, associados e associados às vastatinas, auxiliam na omitização do perfil lipídico. Apesar do grande impacto epidemiológico do HDL-colesterol no risco cardiovascular , estratégias específicas para atuar sobre o HDL não eram disponíveis até o momento. O torcetrapib, um inibidor da proteína de transferência de ésteres de colesterol, promove grandes elevações de HDL-colesterol especialmente em combinação com as estatinas. Terapias biológicas surgem como novas possibilidades e envolvem o uso de proteínas, DNA, anticorpos ou outras substâncias derivadas ou sintétizadas a partir de tecidos vivos com propósitos terapêuticos. O maior avanço em estudos clínicos se deu com a utilização de apolipoproteínas-miméticas, como a apolipoproteína AI Milano, uma variante recombinante de apo AI. Infusões de apo AI Milano reduziram o desenvolvimento da aterosclerose em modelos animais e em humanos. Outras estratégias, como a auto-imunização, formando anticorpos que neutralizam a proteína de transferência de ésteres de colesterol também estão sendo estudadas em ensaios clínicos. Terapia gênica para elevar os níveis de HDL-colesterol pela superexpressão de lecitina:colesterol-aciltransferase encontra-se em perspectiva, mas sua habilidade em prolongar a expressão gênica com segurança irá requerer o desenvolvimento de vetores adequados.

ApoA-I, ApoB y su relación en obesidad infantil: estudio preliminar / Serum apolipoproteins A-I, Apo-Band the ratio Apo A-I/ApoB in obese children: preliminary study

El objetivo de este trabajo es analizar la potencial utilidad de la determinación del nivel sérico de Apoproteína A-I (ApoA-I), Apoproteína B (ApoB) y su relación (ApoA-I/ApoB) como indicadores de riesgo aterogénico, en la obesidad infantil. Para ello se determinaron dichas fracciones, en muestras extraídas en ayunas, en un grupo de 46 escolares obesos según criterio de Peso/Talla y sin patología agregada, por inmunodifusión radial cuantitativa sobre placas (Diffu-Plate). Como valores de referencia se utilizaron los reportados por Feliu-Slobodianik para niños clínicamente sanos de igual edad. Los resultados obtenidos (mg/dL) fueron: ApoA-I = 152,5 ñ 29,3; ApoB = 116,5 ñ 32,7; siendo la relación ApoA-I?ApoB = 1,4 ñ 0,5. Al comparar estos resultados con los respectivos valores de referencia (129,5 ñ 19,9; 83,1 ñ 19,6; 1,7 ñ 0,5), se observó aumento significativo (p < 0,001) en el nivel de las apoproteínas séricas con disminución en su relación; al expresar los resultados como por ciento del valor de referencia, el 95 por ciento de los niños presentó valores superiores al 100 por ciento para estas fracciones; el colesterol total (184,3 ñ 31,7) se encontró por debajo del 95 percentilo según sexo y edad; sólo un 5 por ciento de la población estudiada presentó valores de HDL inferiores al rango de referencia (46,4 ñ 12,6). El aumento en ApoB, apoproteína ligada a LDL está corroborando bioquímicamente, que la obesidad ubica a la población estudiada dentro de las de alto riesgo aterogénico, ratificando la importancia y urgencia del manejo nutricional racional y controlado de este grupo infantil. Por esto, la determinación de ApoB y la relación ApoA-I/ApoB podrían considerarse de utilidad en el seguimiento y control del tratamiento dietoterápico en esta patología nutricional

ApoA-I, ApoB y su relación en obesidad infantil: estudio preliminar / Serum apolipoproteins A-I, Apo-Band the ratio Apo A-I/ApoB in obese children: preliminary study

El objetivo de este trabajo es analizar la potencial utilidad de la determinación del nivel sérico de Apoproteína A-I (ApoA-I), Apoproteína B (ApoB) y su relación (ApoA-I/ApoB) como indicadores de riesgo aterogénico, en la obesidad infantil. Para ello se determinaron dichas fracciones, en muestras extraídas en ayunas, en un grupo de 46 escolares obesos según criterio de Peso/Talla y sin patología agregada, por inmunodifusión radial cuantitativa sobre placas (Diffu-Plate). Como valores de referencia se utilizaron los reportados por Feliu-Slobodianik para niños clínicamente sanos de igual edad. Los resultados obtenidos (mg/dL) fueron: ApoA-I = 152,5 ñ 29,3; ApoB = 116,5 ñ 32,7; siendo la relación ApoA-I?ApoB = 1,4 ñ 0,5. Al comparar estos resultados con los respectivos valores de referencia (129,5 ñ 19,9; 83,1 ñ 19,6; 1,7 ñ 0,5), se observó aumento significativo (p < 0,001) en el nivel de las apoproteínas séricas con disminución en su relación; al expresar los resultados como por ciento del valor de referencia, el 95 por ciento de los niños presentó valores superiores al 100 por ciento para estas fracciones; el colesterol total (184,3 ñ 31,7) se encontró por debajo del 95 percentilo según sexo y edad; sólo un 5 por ciento de la población estudiada presentó valores de HDL inferiores al rango de referencia (46,4 ñ 12,6). El aumento en ApoB, apoproteína ligada a LDL está corroborando bioquímicamente, que la obesidad ubica a la población estudiada dentro de las de alto riesgo aterogénico, ratificando la importancia y urgencia del manejo nutricional racional y controlado de este grupo infantil. Por esto, la determinación de ApoB y la relación ApoA-I/ApoB podrían considerarse de utilidad en el seguimiento y control del tratamiento dietoterápico en esta patología nutricional (AU)

Shared and unique genetic effects among seven HDL phenotypes.

The purpose of this study was to investigate the genetic control of various HDL measures and to determine the proportion of genetic variance explained by shared genes (ie, pleiotropy) and the proportion unique to each trait. The data used were drawn from large, randomly ascertained pedigrees of Mexican Americans participating in the San Antonio Family Heart Study. Data were available for 655 individuals (258 men and 397 women) in 26 families. We performed a multivariate quantitative genetic analysis to simultaneously estimate both the additive genetic and random environmental correlations among seven HDL phenotypes. These seven HDL phenotypes can be divided into two categories: measures of concentration and estimates of particle size. Concentration was measured for apo A-I, apo A-II, esterified cholesterol, and unesterified cholesterol, and particle size was estimated for apo A-I, apo A-II, and esterified cholesterol. The heritabilities (h2) for each of the seven traits were significantly greater than zero (P<.05) and ranged from 0.2 to 0.6. When considered in a pairwise fashion, all combinations of these traits showed marked genetic correlations (rho(G)=0.33 to 0.87) and all were significantly greater than zero (P<.05), indicative of pleiotropic effects. However, we found substantial unique genetic variance for each of these traits even after accounting for the effects shared in common with all the remaining measures. We conclude that the genetic variation in these HDL phenotypes is a result of the action of common as well as unique genes.

Quantificação das apoliproteínas A-I e B em soros normo e hipertrigliceridêmicos, conservados em condições de diferentes temperaturas / Measurement of apolipoproteins A-I and B in normal and hypertriglyceridemic serum stored under different conditions

1.) Utilizando método de imunoturbidimetria, nós medimos as concentrações das apolipoproteínas A-I e B, em amostras de soros normo e hipertrigliceridêmicos, estocados por um período de 94 dias. Alíquotas desses soros foram estocadas a 4°C, -20°C ou em nitrogênio líquido (-170°C). Três “pools” de soros foram usados, contendo respectivamente, 148, 491 e 964 mg/dl de triglicérides (TG). 2.) Nossos resultados mostraram que tanto soros normo quanto hipergliceridêmicos podem ser estocados a 4°C por um período de 8 dias, antes da determinação de apo A-I e apo B por imunoturbidimetria. Com o congelamento a -20°C ou no nitrogênio líquido (-170°C) , as determinações apo A-I foram imediatamente alteradas em 14% no “pool” de soros que continha valores altos de triglicérides, enquanto os outros dois “pools” não mostraram alterações significativas. Os valores de apo B aumentaram em todos os “pools” de soros após o congelamento a -20°C, enquanto no nitrogênio líquido houve significante alteração somente no soro com valores médios e altos de TG.

GPI-specific phospholipase D as an apolipoprotein.

Glycosylphosphatidylinositol-specific phospholipase D (GPI-PLD) has recently been shown to be associated with high-density lipoproteins (HDL) in bovine serum. To determine the distribution of GPI-PLD among lipoproteins and characterize the GPI-PLD-containing lipoproteins in human plasma, we used dextran sulfate and immunoaffinity chromatography to isolate apolipoprotein-specific lipoproteins. This procedure allowed fractionation of lipoprotein particles into those containing apolipoprotein B (Lp B), apolipoproteins AI and AII (Lp AI/AII), or apolipoprotein AI only (Lp AI). In five plasma samples with HDL cholesterol ranging from 40 to 129 mg/dl, 75 +/- 12% (mean +/- SD) of the GPI-PLD activity was associated with Lp AI, 11 +/- 13% with Lp AI/AII, while only 13 +/- 9% was present in plasma devoid of these lipoproteins, suggesting that most of the GPI-PLD in human plasma is associated with apolipoprotein AI. No GPI-PLD activity was detected in Lp B. Further characterization of the GPI-PLD-containing lipoproteins by gel filtration chromatography, nondenaturing poly-acrylamide and agarose gel electrophoresis revealed that GPI-PLD was restricted to an apolipoprotein AI-containing particle or complex that was small (apparent mean Mw of 140 kDa) and distinct from the bulk of HDL. Thus, the majority of plasma GPI-PLD appears to be specifically associated with a small, minor fraction of apolipoprotein AI.

Lipoprotein(a) and apolipoproteins B and A-1 in children and coronary vascular events in their grandparents.

Because premature coronary vascular disease in a first-degree relative increases risk of the disease and the mechanisms may include genetically determined abnormal levels of circulating apolipoproteins, we explored the relationships between schoolchildren's apolipoprotein levels and coronary events in their parents and grandparents. We measured capillary blood concentrations of lipoprotein(a) (Lp(a) and apolipoproteins (apo B and apo A-1) in dried blood spot samples obtained by finger prick from 2010 schoolchildren aged 8 to 12 years, and questioned parents about coronary vascular events in the children's parents and grandparents. Of the 2010 questionnaires sent, 1030 (51%) were returned fully completed. Twenty-three fathers, one mother, and 645 grandparents had had coronary vascular events. There were significant associations between increased Lp(a) levels in children and the numbers of grandparents with coronary vascular events and with increasing grandparent coronary history scores (p < 0.01). There were also positive associations for apo B (p < 0.01) but none for apo A-1. Discriminate analysis showed that the log-transformed Lp(a) level was the variable most predictive of event numbers and of history scores in grandparents (Wilks lambda value = 0.984; p = 0.026); the apo B level was also predictive (Wilks lambda value = 0.988; p = 0.041), but neither the apo A-1 level nor the apo B/A-1 ratio was. We conclude that high Lp(a) and apo B levels in children aged 8 to 12 years are associated with increased risk of coronary vascular disease in older family members, even with a generation gap. These apolipoproteins may largely account for the independent contribution of family history to disease risk. Measurements of Lp(a) and apo B in schoolchildren may help to identify children and their families at increased risk and may facilitate targeting of prevention.

Apoliproteínas A-I y B-100 y enfermedad coronaria comprobada angiográficamente

Objetivo : establecer la correlación de las apolipoproteínas (APO) A-I y B-100 séricas , con la enferemdad coronaria (EC) y su severidad. Método: estudio abierto, prospectivo y análitico en 52 pacientes sometidos a angiocoronariografía de abril a septiembre de 1991, tomando previamente muestra de sangre para medición de colesterol (CT), triglicéridos (TG), HDL, APO-AI y APO B-100 y determinación de LDL, índice aterogénico (IA), LDL/HDL y relación APO A1/B-100. Sitio : Servicio universitario de referencia de pacientes de atención terciaria. Principales resulatdos : 65.4 por ciento de los pacientes fueron hombres y 34.6 por ciento, mujeres; 67.3 por ciento tenían EC y 32.7 por ciento nola tenían. Entre los grupos con y sin EC hubo diferencia significativa en todas las variables medidas, especialmente en el CT, cuya media era de 210+-51 mg por ciento en el grupo sin EC y de 255+-48 mg por ciento en el grupo con EC (p=0.0006), y en la relación APO-AI/B-100, que fue de 2.08+-0.49 para el grupo sin EC y de 1.18+-0.51 para elgrupo con EC (p=0001). Entre hombres y mujeres fueron significativamente diferentes las la APO-AI (p=0.004) y la relación APO-AI/B-100 (p=0.003). Ninguna variable diferenció el grupo con EC leve del grupo sin EC, pero sí diferenciaron la ausencia de EC de lapresencia de EC moderada y severa el CT, APO-AI, APO-AI/B-100, IA y LDL/HDL. En la regresión lineal el grado EC pependió significativamente de APO-AI/B-100 (r=0.73, p<0.001), APO-B-100 (r+0.60, p<0.001), LDL/HDL (r=0.51, p<0.001) y CT (r=0.50, p=<0.001). En la regresión múltiple la presencia de EC dependió de la relación APO-AI/B-100 (r=0.73) y del colesterol total (r=0.50). Conclusiones : el índice APO-AI/B-100 mejoró de manera importante la correlación con la presencia de EC con respecto a las demás variables, no así la medición de APO-AI y B-100 por separado. Esta misma relación no discriminó la ausencia de EC de la EC leve, pero si la ausencia de EC de la EC moderada y severa.

A multicentre comparative study of serum lipids and apolipoproteins in long-term users of DMPA and a control group of IUD users. World Health Organization. Task Force on Long-Acting Systemic Agents for Fertility Regulation Special Programme of Research, Development and Research Training in Human Reproduction.

A clinical trial was conducted in three centres to assess the effects of long-term use of the injectable contraceptive depot-medroxyprogesterone acetate (DMPA) on lipid metabolism. Fifty women who had used DMPA at a dose of 150 mg every three months for 3 to 9 years were recruited in Bangkok, Christchurch and Mexico City. They were compared to a control group of 120 IUD users. Total cholesterol, LDL-cholesterol, HDL-cholesterol, total triglycerides, apolipoproteins AI, AII and B were measured throughout one injection interval. Significant findings differed between centres. Compared to their own centre controls, DMPA users in Bangkok had higher LDL-cholesterol levels; those in Christchurch had lower HDL-cholesterol, apolipoprotein (apo) AI and apo AI/B ratio and higher apo B levels; those in Mexico City had a lower apo AI/B ratio. Further changes were observed during the injection interval, some of which were correlated to changes in serum MPA levels. It is concluded that long-term use of DMPA induces moderate changes in lipid metabolism which are unfavourable in terms of risk for atherosclerosis. This should be borne in mind when weighing the overall risks and benefits of this contraceptive method for a potential user.