Hiperinsulinemia y resistencia insulínica en niños de dos escuelas públicas de Oaxaca, México / Hyperinsulinemia and insulin resistance in children

Background: Obesity during childhood is a risk factor for developing cardiovascular diseases during adulthood. Aim: To measure insulin and glucose levels and parameters of insulin resistance in obese, overweight and normal weight Mexican children. Material and Methods: Comparative study of 21 obese children with a body mass index (BMI) over percentile 95, aged 10 ± 1 years (10 males), 14 children aged 10 ± 2 (7 males) with a BMI between percentiles 85 and 94 and 16 children aged 9 ± 2 years (3 males) with a body mass index between percentiles 10 and 84. Body weight, blood pressure and waist circumference were measured and a blood sample was obtained to measure fasting glucose and insulin levels. Homeostasis model of insulin resistance (HOMA) and quantitative insulin sensitivity check index (QUICKI) were calculated. Results: Among obese, overweight and normal weight children, insulin levels were 14.9 (95% CI 10.90-18.99), 7.20 (CI 5.12-9.28) and 4.73 (CI 95% 1.92-7.53) uU/ml, respectively. The figures for HOMA were 3.16 (95% CI 2.20-4.12), 1.49 (95% CI 1.03-1.94) and 0.97 (95% CI 0.35-1.60), respectively. The figures for QUICKI were 0.331 (95% CI 0.319-0.343), 0.371 (95% CI 0.349-0.393) and 0.419 (95% CI 0.391-0.446), respectively. Compared to their normal weight counterparts, the risk of obese children and those with a waist circumference over percentile 90 of having a HOMA over 3.16 was 17 and 10 times higher, respectively. BMI correlated better than waist circumference with insulin levels. Conclusions: Obese children have higher levels of insulin resistance than their normal weight counterparts.

[Bone mineral density and 17 beta-estradiol correlation in postmenopausal women]. / Correlación entre la densidad mineral ósea y el 17beta-estradiol sérico en mujeres postmenopáusicas.

BACKGROUND: With the increased life-expectancy reached during 20th century, women will spend a very important part of their lives in the estrogenic deficiency state accompanying menopause. OBJECTIVES: To detect serum 17beta-estradiol levels, bone mineral density values, and to see the correlation between both parameters as well as with postmenopausal period. MATERIAL AND METHODS: A transversal study with ambulatory, community-dwelling postmenopausal women from Oaxaca de Juárez, Oax. was performed. RESULTS: We studied 70 women with spontaneous menopause, medium values were: age, 55.9 +/- 5.4 yr; menopause age, 48 +/- 3 yr; postmenopausal period, 7.9 +/- 5.3 yr; body mass index, 28.3 +/- 5.4, and serum 17beta-estradiol by radioimmunoassay, 62.78 +/- 25.83 pg/mL. Quantitative calcaneous ultrasound was used to measure bone mineral density and we found 30 women with normal level (-1.0 to 1.4 SD), 29 with osteopenia (-1.1 to -2.3 SD) and only 2 subjects with osteoporosis (-2.7 to 2.8 SD). CONCLUSIONS: Statistical analysis shows that bone mineral density and postmenopausal period were significantly correlated (p<0.05) as well as serum 17beta-estradiol levels with postmenopausal period; nevertheless, no correlation between bone mineral density and serum 17beta-estradiol or body mass index (p>0.05) was found. On the other hand, it is remarkable high serum 17beta-estradiol levels found in this group, related with postmenopausal status. These latter results are different from those reported in the literature.

[Bibliographic review. The role of hypoestrogenism in postmenopausal osteoporosis--new perspectives]. / Artículo de revisión bibliográfica. Papel del hipoestrogenismo en la osteoporosis posmenopáusica: nuevas perspectivas.

Estrogen deficiency following menopause results in a significative bone loss, which is thought to be the result of an imbalance in bone remodeling process between formation activity and resorption, where the later is functionally higher than normal and could develop osteopenia or osteoporosis type I. Although it has been made a lot of scientific investigations to explain the way by hypoestrogenism affect skeleton, the renal mechanism remains unclear and it seems to be multifactorial. Therefore, the purpose of this review is to analyze the new perspectives about the effects of serum estradiol levels on bone tissue; special emphasize is made concerning the role of: estrogen receptors, cytokines, RANKL/RANK/OPG system, PTH and PTHrP, bone turnover markers, osteocytes apoptosis, estrogens serum levels and its metabolic pathways.