[Clinical and metabolic features of subjects with glucose intolerance and high fasting glucose levels]. / Características clínicas y metabólicas de los estados de intolerancia a la glucosa y glicemia de ayuno alteradas.

BACKGROUND: Subjects with glucose intolerance or high fasting glucose levels have a higher cardiovascular risk and frequently become diabetic. AIM: To assess clinical and metabolic characteristics of patients with glucose intolerance or high fasting glucose levels. MATERIAL AND METHODS: Fasting and post glucose load serum glucose and insulin levels were measured in 1404 people, aged 42,0 +/- 14,2 years (81% women) with high diabetic risk. We categorized subjects in different alterations of blood glucose, according to 2006 American Diabetes Association categories. Insulin resistance (RI), insulin secretion (beta %) and insulin disposition (ID), were calculated using fasting blood glucose and insulin levels, using the homeostasis model assessment (HOMA I and II). RESULTS: Sixty percent of studied subjects had first grade relatives with diabetes mellitus and 1097 (78%) were categorized as normal (N), 45 (3%) as Diabetes Mellitus (DM), 161 (11%) as high fasting glucose levels (GAA) and 103 (7%) as glucose intolerant (ITG). Fifty three of the 106 subjects with GAA (50%), were also glucose intolerant. Subjects with GAA had similar insulin sensitivity and lower beta cell function than N (insulin disposition 58 +/- 12 and 111 +/- 32%, respectively p < 0.01). ITG had less insulin sensitivity than N (HOMA-IR 2.6 +/- 1.50 +/- and 2.0 +/- 1.30, respectively) and only a mild decrease in beta cell function (insulin disposition 96 +/- 26 and 111 +/- 32% respectively, p < 0.01). Patients GAA plus ITG had similar alterations than those with DM (HOMA-IR 3.8 +/- 2.2 and 4.4 +/- 3.7 respectively; insulin disposition 57 +/- 10 and 56.0 +/- 26% respectively. CONCLUSIONS: Patients with higher fasting glucose levels behave differently from those with glucose intolerance. High fasting glucose levels are highly prevalent in subjects with high risk of DM and must be considered as risk indicator in preventive programs for diabetes mellitus.

Intolerancia a la glucosa en niños obesos: comunicación preliminar / Glucose intolerance in obese children

Background: Glucose intolerance (GI) is preceded by a prolonged period of Insulin Resistance (IR) and is an advanced stage towards the development of Type 2 Diabetes Mellitus (NIDDM), whose incidence is increasing in the pediatric population, along with obesity. Aim: To describe clinical and metabolic characteristics of obese children according to their glucose tolerance. Patients and Methods: We studied 52 obese children, aged 8 to 17 years, with a body mass index z-score of 4.7±1.6. An oral glucose tolerance test with insulin measurements in the basal period and at 30 minutes, was done. IR was estimated through the Homeostasis Model Assessment index (HOMA) and insulin secretion through the Insulinogenic Index. Results: Six children (11.5 percent) had GI. When compared with children with normal glucose tolerance, children with GI had similar clinical features, similar HOMA (5.4±3.3 and 5.2±2.0 respectively) and basal insulinemia (23.4±11 and 24.6±10 ÁU/ml). But they had lower insulin level at 30 min (128±61 and 253.7±357 ÁU/ml respectively, p >0.05) a lower Insulinogenic Index (1.44±0.4 and 4.4±1.0 ÁU/ml/mg/dl, p <0.05), a higher total cholesterol (192±37 vs 168±34 mg/dl, p <0.05) and a higher LDL cholesterol (123±35 and 101±28 mg/dl, respectively, p <0.05). Conclusions: Obese children with or without GI have similar clinical features and body mass index. In severe obese children with marked IR, the appearance of Glucose Intolerance seems to be associated to a decrease in insulin secretion and not to an increase in IR

Resistencia insulínica y otras expresiones del síndrome metabólico en niños obesos chilenos / Insulin resistance in obese Chilean children

Background : Infantile obesity is a probable risk factor for the early appearance of chronic illnesses like Type 2 Diabetes Mellitus, Dislipidemia and Hypertension. Insulin Resistance (IR) appears as the common etiological mechanism. Aim : To describe metabolic complications associated to obesity in a group of Chilean children and to correlate them with IR, estimated through the homeostasis model assessment index (HOMA). Subjects and methods: We studied 88 children, 12ñ2.4 years old. Fifty two had severe obesity, 19 were overweight, and 17 had a normal weight (body mass index z score (BMIz): 4.7ñ1.6, 1.7ñ0.5 and 0.2ñ0.6 respectively, p <0.001). In obese children, an oral glucose tolerance test, measuring basal and 30 min insulin levels, was performed and serum lipid levels were measured. Results: Eleven percent of the severely obese children were glucose intolerant, 67 percent had basal hyperinsulinemia (>20 uU/ml) and 79 percent had IR (HOMA >3.8). These children also had a higher prevalence of acantosis nigricans than the overweight and normal counterparts (63, 10.5 and 0 percent respectively, p <0.001), higher basal insulinemia: (24.4ñ10, 16.4ñ4 and 12.2ñ3 mU/ml respectively) and HOMA (5.3ñ2, 3.4ñ0.8 and 2.3ñ0.5 respectively, p <0.001). By multiple stepwise regression analysis, BMIz was the only significant predictor for basal hyperinsulinemia, HOMA and diastolic blood pressure. Age and BMIz were independent predictors for systolic blood pressure. The strongest predictor for plasma lipid levels was the family history of dislipidemia. Conclusions: Obese children have a high prevalence of metabolic complications, which are related to the severity of obesity. Most of the severely obese children have hyperinsulinism and IR. BMIz is the principal predictor for high blood pressure. Familiar history is the better predictor for dislipidemia

Comparación de la acción antioxidante de estriol y estradiol in vitro sobre lipoproteínas de baja densidad en mujeres postmenopáusicas / Comparison of antioxidant actions of estriol and estradiol on low density lipoproteins in post menopausal women

Background: Estradiol (E2) has a potent antioxidant effect on low density lipoproteins (LDL) in vitro and in vivo, which could be important in explaining the cardioprotective effect of hormone replacement therapy (HRT) in post menopausal women. Estriol (E3), on the other hand, is a weak estrogen with low metabolic effects on different tissues, and at present no cardioprotective effect has been attributed to this steroid. Aim: To study the antioxidant effect of E3 on LDL and to compare it with the potent antioxidant action exhibited by E2. Subjects and methods: After LDL was isolated by ultra centrifugation from plasma of 12 healthy untreated post menopausal women, it was divided into aliquots containing 0.5 mg of LDL protein. Estriol and E2 in doses of 0, 1, 5, 15 and 50 µM were incubated with different aliquots of LDL. CuSO4 15 µM was added to each aliquot to induce an oxidative stress. The aliquots were then incubated during 4 hours at 37 ­C. Malonaldehyde (MDA) was measured as a marker of LDL oxidation, and expressed as nM/mg protein. Results (mean ñ SD): Estriol induced a dose-dependent decrease in MDA concentration (baseline 62.8 ñ 21.7; 1 µM: 61.5 ñ 23.0; 5 µM: 52.9 ñ 20,3; 15 µM 43.5 ñ 20.1 and 50 µM: 31.0 ñ 17.6 nM/mg protein; F= 92.4; p< 0.0001), reaching a mean decrease of 50.7 percent at the highest dose tested. Estradiol has a similar dose-dependent decrease in MDA concentration (F= 60.2; p< 0.0001), revealing a more potent effect than E3 (p< 0.05), with a mean decrease of 67.4 percent at the highest dose tested. Conclusions: Our results demonstrate that estriol shows an important antioxidant action of LDL in vitro, although its effect is less potent than estradiol. These results raise the possibility that estriol could have a cardioprotective effect in post menopausal women, possibility that has not been yet demonstrated

Nutrición y cardiopatía: mitos y realidades / Diet and coronary heart disease: myths and facts

La relación directa entre la dieta y la cardiopatía coronaria ha sido motivo de controversia ya que los resultados de los estudios de intervención realizados hasta ahora han sido conflictivos. Aunque antiguamente el colesterol de la dieta era considerado muy peligroso en la etiopatogenia de la cardiopatía coronaria, estudios más recientes han indicado que el colesterol de la dieta en individuos sanos no tiene la importancia previamente otorgada. Estudios en los cuales se ha determinado el efecto del tipo de grasa en el colesterol sanguíneo han mostrado que los ácidos láurico, mirístico y palmítico tienden a elevar el colesterol total y el colesterol LDL, mientras que el esteárico los reduce levemente. El trans-ácido elaídico eleva el colesterol total y el del LDL, y además reduce el colesterol HDL. El ácido oleico reduce el colesterol total y el de LDL y aumenta el colesterol HDL. En general las recomendaciones internacionales indican un aporte de grasa menor de un 30 por ciento de las calorías totales, dividido igualmente entre ácidos grasos monoinsaturados, poliinsaturados y saturados. Se discute además el efecto de la fibra dietaria y de los antioxidantes en la cardiopatía coronaria

Dislipidemias en enfermedades renales: etiopatogenia y tratamiento / Dyslipidemias in renal diseases: pathogenesis and treatment

Patients with renal diseases like nephorotic syndrome, chronic renal failure (uremia) and renal transplantation frequently present disturbances of lipid metabolisms, howerer their pathogenesis is partially understood. Moreover, cardiovascular diseases are responsible for many deaths in these patients. Although the effect of the dyslipidemias in the development of atherosclerosis in renal diseases is not clear, they probably play a role. Since actually the survival of these patients is substantial, it is important to manage them appropriately with regard to their dyslipidemias. this review will examine the pathogenesis and treatment of dyslipidemias in patients with nephrotic syndrome, chronic renal failure and renal transplantation

Neuropatía diabética: sensibilidad térmica y control metabólico en diabéticos no insulinodependientes / Diabetic neuropathy: thermal sensation and metabolic control in non insulin dependent diabetics

Background: The early detection of peripheral neuropathy in diabetics is important since it is the main riskfactor for lower limb trophic lesions in diabetics. Aim: To assess the relationship between feet thermal sensation threshold and metabolic control in ambulatory non-insulin-dependent diabetics. Pattients and methods: A random sample of 34 non-insulin-dependent diabetic followed for more than five years in a special clinic, out of 368 patients, was selected. Warmth sensation thresbolds were measured in the dorsum of booth feet using a MSTP-III thermostimulator The average value of all glycosylated hemoglobins obtained during the 9.7 ñ 5.3 years of follow up for each patient was calculated. A multiple stepwise regression analysis was performed between thermal sensation as the dependent variable and glycosylated hemoglobin, fasting blood glucose, age and diabetes duration. Results: The regression model disclosed glycosylated hemoglobin as the only independent predictor of warmth sensation threshold (partial r= 0.385; p= 0.043). Fifteen diabetic patients with metabolic control, defined as those with a mean glycosylated hemoglobin of less than 9.5 percent, had a warmth sensation threhold of 35.6 ñ 3.7 ºC, whereas 19 diabetics with a bad control (glycosylated hemoglobin 9.5 percent) had a threshold of 39 ñ 3.8 ºC(p= 0.017). Conclusions: In this group of diabetics there is a relationship between the severity of distal polyneuropathy and the metabolic contrl, assessed with glycosylated hemoglobin levels

El problema de la obesidad y sus características alarmantes en Chile / The problem of obesity in Chile: some shocking characteristics

Obesity is a disease which severely affects health associated to an increase in relative mortality. The measurement of obesity is currently performed by means of the Body Mass Index (BMI). Normal BMI values are between 20 and 24,9 kg/m2. In obese individuals a central fat distribution is associated with an increased mortality in men and probably in women when compared with a peripheral distribution. Based on studies carried out in the Metropolitan Region (Greater Santiago) in 1992, it is estimated that the prevalence ofobesity in the population is near 20 percent in men and 40 percent in women, with the bighest prevalence being observed in women from a low socioeconomic level. The projection of these figures to the whole country gives an estimate of 2.5 million people in Chile with an increased risk of mortality due to obesity. Since there is a lack of awareness in the chilean population of the pathology of obesity and its consequences, the implementation of programs of preventions and treatment of this disease lead by the health authorities is of paramount importance

Marcadores inmunológicos y de secreción insulínica en pacientes diabéticos no insulino dependientes con fracaso secundario a drogas hipoglicemiantes orales / Immunologic and insulin secretion markers in diabetic non insulin dependent patients with secondary failure to oral hypoglycemic agents

The pathogenesis of secondary failure to hypoglycemic agents is heterogenous. Some patients are true insulin dependent diabetics with a slow autoimmune disease suggested by their positive islet cell antibodies. Others, have an increased insulin resistance. To assess the frequency of positive islet cell antibodies in diabetic patients with secondary failure to oral hypoglycemic agents. 31 diabetics, 16 with recent (less than six months) secondary failure and 15 with metabolically stable non insulin dependent diabetes were studied. All patients were older than 25 years old and had a body mass index of less than 30 kg/m2. C peptide levels before and at 5,15 and 30 min after IV glucagon, islet cell antibodies using the Poly Human IgG peroxidase method an insulin sensitivity and secretion (estimated by the Homeostasis Model Assessment) were measured. Patients with secondary failure had lower C peptide levels compared to subjects with stable diabetes (basal: 1.5ñ0.2 and 2.8ñ0.2 ng/ml; 5 min: 2.4ñ0.3 and 5.5ñ0.5 ng/ml; 15 min:1.9ñ0.3 and 4.0ñ0.6 ng/ml; 30 min:1.6ñ0.3 and 3.4ñ0.5 ng/ml). Beta cell activity was 20.6ñ4.3 percent in patients with secondary failure and 92.2ñ9 percent in stable diabetics (p<0.01). Insulin sensitivity was similar in both groups (48.6ñ6 and 42.8ñ3.5 percent respectively). Three patients with secondary failure and none with stable diabetes had positive islet cell antibodies. When comparing patients with secondary failure and positive antibodies and subjects with secondary failure and negative antibodies, the former had non significantly lower age, BMI and C peptide levels. Some diabetic patients with secondary failure have positive islet cell antibodies. They should be measured in these patients to start insulin treatment precociously

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