Reinehr Thomas, de Sousa Gideon, Alexy Ute, Kersting M, Andler Werner
Vestische Hospital for Children and Adolescents Datteln, University of Witten/Herdecke, Dr F Steiner Strasse 5, 45711 Datteln, Germany.
Eur J Endocrinol. 2007 Aug;157(2):225-32. doi: 10.1530/EJE-07-0188.
The roles of vitamin D and parathyroid hormone (PTH) are discussed controversially in obesity, and studies of these hormones in obese children are limited. Therefore, we studied the relationships between PTH, 1,25-dihydroxy-vitamin D (1,25-OH Vit D), 25-hydroxy-vitamin D (25-OH Vit D), weight status, and insulin sensitivity before and after weight loss in obese children.
Fasting serum PTH, 1,25-OH Vit D, 25-OH Vit D, inorganic phosphate, calcium, alkaline phosphatase (AP), insulin, glucose, and weight status (SDS-BMI and percentage body fat) were determined in 133 obese children (median age 12.1 years) and compared with 23 non-obese children. Furthermore, these parameters were analyzed in 67 obese children before and after participating in a 1-year obesity intervention program.
Obese children had significantly (P < 0.001) higher PTH and lower 25-OH Vit D concentrations compared with non-obese children, while calcium, phosphate, AP, and 1,25-OH Vit D did not differ significantly. Changes of PTH (r = 0.23, P = 0.031) and 25-OH Vit D (r = -0.27, P = 0.013) correlated significantly with changes of SDS-BMI, but not with changes of insulin sensitivity (homeostasis model assessment; HOMA-B%). Reduction of overweight in 35 children led to a significant (P < 0.01) decrease of PTH concentrations and an increase in 25-OH Vit D levels.
PTH levels were positively and 25-OH Vit D concentrations were negatively related to weight status. Since these alterations normalized after weight loss, these changes are consequences rather than causes of overweight. A relationship between PTH, vitamin D, and insulin sensitivity based on the HOMA index was not found in obese children. Further longitudinal clamp studies are necessary to study the relationship between vitamin D and insulin sensitivity.
维生素D和甲状旁腺激素（PTH）在肥胖症中的作用存在争议，且针对肥胖儿童中这些激素的研究有限。因此，我们研究了肥胖儿童体重减轻前后PTH、1,25 - 二羟维生素D（1,25 - OH Vit D）、25 - 羟维生素D（25 - OH Vit D）、体重状况和胰岛素敏感性之间的关系。
测定了133名肥胖儿童（中位年龄12.1岁）的空腹血清PTH、1,25 - OH Vit D、25 - OH Vit D、无机磷、钙、碱性磷酸酶（AP）、胰岛素、葡萄糖和体重状况（SDS - BMI和体脂百分比），并与23名非肥胖儿童进行比较。此外，对67名肥胖儿童在参加为期1年的肥胖干预项目前后的这些参数进行了分析。
与非肥胖儿童相比，肥胖儿童的PTH显著更高（P < 0.001），25 - OH Vit D浓度显著更低，而钙、磷、AP和1,25 - OH Vit D无显著差异。PTH的变化（r = 0.23，P = 0.031）和25 - OH Vit D的变化（r = -0.27，P = 0.013）与SDS - BMI的变化显著相关，但与胰岛素敏感性的变化（稳态模型评估；HOMA - B%）无关。35名儿童超重的减轻导致PTH浓度显著降低（P < 0.01），25 - OH Vit D水平升高。
PTH水平与体重状况呈正相关，25 - OH Vit D浓度与体重状况呈负相关。由于这些改变在体重减轻后恢复正常，所以这些变化是超重的后果而非原因。在肥胖儿童中未发现基于HOMA指数的PTH、维生素D和胰岛素敏感性之间的关系。需要进一步进行纵向钳夹研究来探讨维生素D与胰岛素敏感性之间的关系。
