Shaibi Gabriel Q, Davis Jaimie N, Weigensberg Marc J, Goran Michael I
Department of Kinesiology, Arizona State University, Phoenix, AZ, USA.
Int J Pediatr Obes. 2011 Jun;6(2-2):e290-6. doi: 10.3109/17477166.2010.528766. Epub 2010 Nov 11.
The purpose of this investigation was to compare the homeostasis model assessment of insulin resistance (HOMA-IR) to more direct measures of insulin action before and after lifestyle interventions in obese Latino youth.
Eleven obese Latino boys (age 15.1 ± 1.6 years, body mass index (BMI) percentile 97.3 ± 3.5%) and twenty obese Latina girls (age 14.7 ± 1.8 years, BMI percentile 96.6 ± 3.6%) participated in two distinct lifestyle interventions. Boys participated in a 16-week exercise intervention and girls participated in a 12-week nutrition education program. Insulin sensitivity was determined by the frequently sampled intravenous glucose tolerance test (FSIVGTT) in boys and by a 3-hour oral glucose tolerance test with multiple sampling calculations for the whole-body insulin sensitivity index (WBISI) in girls. HOMA-IR was measured for both groups.
HOMA-IR was correlated at baseline to the FSIVGTT (r = -0.57, p = 0.07) and the WBISI (r = -0.78, p<0.01) and at follow-up (FSIVGTT: r = -0.81, p<0.003; WBISI: r = -0.71, p = 0.001). Post-intervention, insulin sensitivity increased 45% in the boys and 34% in the girls; however, these improvements were not reflected by significant changes in HOMA-IR.
Improvements in insulin sensitivity following an intervention measured either by the FSIVGTT or an OGTT were not detected by HOMA-IR. Researchers and clinicians should exercise caution in relying on fasting indices, such as HOMA-IR, to determine the impact of lifestyle interventions on insulin sensitivity in overweight youth.
本研究旨在比较肥胖拉丁裔青少年在生活方式干预前后，胰岛素抵抗的稳态模型评估（HOMA-IR）与更直接的胰岛素作用测量指标。
11名肥胖拉丁裔男孩（年龄15.1±1.6岁，体重指数（BMI）百分位数97.3±3.5%）和20名肥胖拉丁裔女孩（年龄14.7±1.8岁，BMI百分位数96.6±3.6%）参与了两项不同的生活方式干预。男孩参加了为期16周的运动干预，女孩参加了为期12周的营养教育项目。通过频繁采样静脉葡萄糖耐量试验（FSIVGTT）测定男孩的胰岛素敏感性，通过3小时口服葡萄糖耐量试验及多次采样计算全身胰岛素敏感性指数（WBISI）来测定女孩的胰岛素敏感性。两组均测量了HOMA-IR。
HOMA-IR在基线时与FSIVGTT（r = -0.57，p = 0.07）和WBISI（r = -0.78，p<0.01）相关，在随访时与FSIVGTT（r = -0.81，p<0.003；WBISI：r = -0.71，p = 0.001）相关。干预后，男孩的胰岛素敏感性提高了45%，女孩提高了34%；然而，这些改善并未在HOMA-IR的显著变化中体现出来。
通过FSIVGTT或OGTT测量的干预后胰岛素敏感性的改善，HOMA-IR并未检测到。研究人员和临床医生在依靠空腹指标（如HOMA-IR）来确定生活方式干预对超重青少年胰岛素敏感性的影响时应谨慎。
