Síndrome metabólico en niños y adolescentes: asociación con sensibilidad insulínica y con magnitud y distribución de la obesidad / Prevalence of metabolic syndrome in a sample of Chilean children consulting in an obesity clinic

Background: In Chile between 1986 and 1998, the prevalence of obesity has increased from 4.6 percent to 24 percent in prepuberal and from 2.3 percent to 17 percent in puberal children. Aim: To assess the prevalence of metabolic syndrome (MS) in a sample of obese and overweight Chilean children. Patients and methods: Descriptive study in 489 children (273 females), aged from 6 to 16 years, consulting in an obesity program. Body mass index, Tanner puberal development, waist circumference, blood pressure, fasting blood glucose, insulin and lipid levels were measured. Insulin sensitivity was calculated using the mathematical models QUICKI and HOMA. MS was diagnosed when three or more of the following criteria were met: a waist circumference over percentile 90, a blood pressure over percentile 90, serum triglycerides over 110 mg/dl, HDL cholesterol of less than 40 mg/dl or a fasting blood glucose level over 100 mg/dl. Results: MS was present in 4 percent of children with overweight and 30 percent of obese children. No differences in prevalence were observed for sex or puberal development. The most prevalent cardiovascular risk factors were abdominal obesity, present in 76 percent of the sample and high triclycerides levels in 39 percent. The less prevalent risk factor was a fasting blood glucose over 100 mg/dl in 3.7 percent. The risk for MS increased ten fold in children with severe obesity, compared with those with overweight. Those with abdominal obesity had a 17 times higher risk of MS. Basal insulin sensitivity was significantly associated with the number of cardiovascular risk factors and the presence of MS. Conclusions: In this sample of children, fat distribution and the severity of obesity were strong determinants of MS. Waist circumference had a higher impact on MS than body mass index.

Pacientes con limitación crónica al flujo aéreo: efectos del entrenamiento muscular respiratorio con válvula de carga umbral construída con tecnología apropiada, asociado a apoyo nutricional / Patients with chronic airflow limitation: effects of muscular respiratory training with threshold load valve constructed according to appropriate technology, associated to nutritional support

To assess prospectively the effects of a controlled program of inspiratory muscle program and nutritional support in patients with chronic obstructive lung disease (COPD). 23 patients with COPD were randomly assigned into 4 groups. Group I received a 1000 kcal/day nutritional supplement, given as a casein based enteral nutritional formula; group III was subjected to inspiratory muscle training, using an inexpensive pressure threshold load valve constructed according to appropriate technology principles of the WHO, adjusted at 30 percent of Maximal Inspiratory Mouth Pressure and received also the nutritional supplement; group IV was trained but did not receive the nutritional supplement and group II was not trained nor supplemented. Patients were studied during 3 months and monthly, inspiratory muscle function, exercise capacity and antropometry were measured. A significant improvement in exercise capacity, maximal inspiratory pressure and inspiratory muscle endurance was observed in the 4 groups throughout the study. Trained subjects had greater improvement in their inspiratory muscle endurance, compared to untrained subjects. Nutritional support had no effect in inspiratory muscle function or exercise capacity. No changes in antropometric measures were observed. The pressure threshold load valve used in this study, improved inspiratory muscle endurance and nutritional support had no effect in patients with COPD