Evaluación ultrasonográfica de la función endotelial en niños y adultos chilenos / Ultrasound assessment of endothelial function in Chilean children and adults

Background: Endothelial dysfunction is an important pathogenetic mechanism in the development of atherosclerosis. Aim: To evaluate endothelial function in Chilean children and adult subjects and to provide normal values of flow mediated dilatation (FMD) in the Chilean population. Subjects and Methods: Flow mediated dilation of the brachial artery was measured by high resolution ultrasonography in healthy children (n=32) and adults (n=69) of both gender, in a group of 8 healthy women during 4 periods of pregnancy and late postpartum, and in 22 men and women with a history of stroke or coronary heart disease. Results: FMD in boys and girls was 9.9±3.6 and 10.0±4.2% respectively (NS). The figures for young women and young men were 11.3±3.8 and 8.6±3.9, respectively (p=0.02); for postmenopausal women and older men, 5.5±6.6 and 7.6±6.7 respectively (NS). During normal pregnancy and postpartum there were no significant changes in FMD. Patients with cardiovascular disease had a FMD of 0.3±5.2%, (p <0.001, with other groups). Conclusions: The present study provides values of FMD in healthy Chilean subjects of different ages, and in patients with coronary heart disease.

Determinación del índice de resistencia insulínica mediante HOMA en una población de la Región Metropolitana de Chile / Measurement of insulin resistance using the homeostasis model

Background: Insulin resistance is defined as an inappropriate high level of plasma insulin required to maintain metabolic homeostasis. It is associated with type 2 diabetes and cardiovascular diseases. The glucose clamp technique is the standard method for the measurement of insulin resistance. However, this method is laborious, expensive and impractical to perform in epidemiological investigations. The homeostasis model assessment (HOMA) has been proposed to assess insulin resistance and secretion, using fasting glucose and insulin concentrations. Aim: To measure insulin resistance using HOMA (HOMAir) in a population sample from the Metropolitan Region in Chile. Material and Methods: One hundred twenty subjects (59 female) with a normal body mass index and fasting blood glucose were studied. Fasting plasma glucose was measured by a glucose oxidase method and serum insulin was measured by radio immunoassay. Results: Fasting blood glucose was 81.6ñ9.4 mg/dl and serum insulin was 9.7ñ2.4 µU/ml. Mean HOMA insulin resistance was 1.96ñ0.57 (range 0.5 and 3.0). Conclusions: These HOMA values can be used as reference for Chilean non obese individuals

Diferencias en antioxidantes plasmáticos según nivel socioeconómico en mujeres chilenas / Differences in plasma antioxidants according to socioeconomic level in chilean women

Background: Free radical-mediated oxidative damage is a known initial event in atherogenesis. Cardiovascular disease is frequent in the Chilean population showing differences in the prevalence of risk factors of the disease according to socioeconomic level (SEL). Aim: To determine levels of antioxidants and lipid peroxides in Chilean women from different SEL. Patients and methods: Blood samples were taken from 81 women for measurements of plasma ascorbic acid, ß-carotene, a-tocopherol, licopene, ubiquinol, glutathione, total plasma antioxidant capacity, and lipid peroxides (TBARS). Results:Individuals in the lower SEL showed reduced levels of plasma ß-carotene, ascorbic acid, a-tocopherol, and ubiquinol compared to women in the higher SEL. There were no differences between groups in the plasma levels of glutathione, total antioxidant capacity, or TBARS. Conclusions: The results could be explained in part by the higher consumption of fruits and vegetables in women from the upper SEL

Ingesta de nutrientes en vegetarianos chilenos / Nutrient intake in chilean vegetarians

El consumo de alimentos en vegetarianos ha sido estudiado en forma muy limitada en Chile. En este estudio se midió la ingesta alimentaria en 27 vegetarianos (VT) comparándola con 27 omnívoros (OM), pareados por índice de masa corporal, sexo y edad. El consumo diario fue determinado con encuestas por recordatorio de 24 horas tomando el promedio de 3 días. La ingesta promedio de calorías en VT fue de 1.613 cal/día, que no fue significativamente diferente de OM. El consumo de grasas en VT fue significativamente menor que en OM (37,7 ñ 13.2 g en VT y 46,6 ñ 22,0 g en OM, p<0,01), al igual que el consumo de colesterol (72,5 ñ 52,0 y 192 ñ 111, p<0,001). La ingesta de fibra fue significativamente mayor en VT que en OM (26,7 ñ 12,7 g y 14,4 ñ 6,6 g, p<0,01). Los VT consumen significativamente más caroteno y vitamina C y menos vitamina B12 que los OM. El consumo promedio de calcio fue similar y muy bajo en VT y OM (635 y 655 mg, respectivamente)

Vino y salud: estudios epidemiológicos y posibles mecanismos de los efectos protectores / Wine and health: epidemiological studies and possible mechanisms for protective effect

Epidemiological studies show that moderate alcohol consumption, particularly wine, is associated to a decreased risk of ischemic heart disease death. A series of in vitro observations also support this association. Low density lipoproteins (LDL) oxidation apparently plays a key pathogenic role. Wine contains compounds with antioxidant capacity that could account for its postulated stabilizing effect on LDL. Furthermore, in human volunteers wine increases plasma total antioxidant capacity. Other additional effects also contribute to decrease the risk of ischemic heart disease: increased HDL cholesterol, and decreased blood coagulation. In another series of observations, moderate alcohol consumption has been associated with decreased physical and mental deterioration in elderly people. However, it is still under analysis if exaggerated alcohol consumption does increase the incidence of some cancers. On the whole, the presently available evidences clearly indicate that the posittive effects associated to moderate wine or alcohol consumption, predominate over the negative effects. In fact, it seems reasonable to reassure moderate alcohol consumers that their cardiovascular death risk is lower; yet there are not enough studies to recommend moderate drinking to non-drinkers

Indicadores de riesgo de aterosclerosis: evaluación mediante coronariografía en hombres no diabéticos con colesterol total igual o menor a 240 mg/dl / Index of atherosclerosis risk: evaluation by coronariography in non diabetic males with total cholesterol same or less than 240 mg/dl

We studied 90 male non diabetic patients aged between 40 and 65 years old with a total cholesterol of less than 240 mg/dl and not receiving cholesterol reducing drugs, that were subjected to elective coronary arteriography. Weight, height, blood pressure and smoking habits were recorded and a fsting blood sample was drawn to mesure total and HDL cholesterol, triglycerides, apoproteins A! and B, Lipoprotein(a) and plasma cholesteryl ester transfer activity. Arteriography disclosed coronary lesions in 54 patients. Compared to patients without lesions, the former had lower HDL cholesterol (34 ñ 9.8 vs 40.2 ñ 11.6 mg/dl) and higher total cholesterol/HDL, cholesterol and apoB/apoA1 ratios. No differences were found for lipoprotein(a) and plasma cholesteryl ester transfer activity. Unvariate analysis showed that low HDL cholesterol had the best predictive capacity for atherosclerosis