Lower insulin sensitivityremains a feature of children born very preterm.

BACKGROUND The first report of children born very preterm (<32 weeks of gestation) having insulin resistance was made 16 years ago.However, neonatal care has improved since. Thus, we aimed to assess whether children born very preterm still have lower insulin sensitivity than term controls. METHODS Participants were pre-pubertal children aged 5-11 years born very preterm (<32 weeks of gestation; n=51; 61% boys) or at term (37-41 weeks; n=50; 62% boys). Frequently sampled intravenous glucose tolerance tests were performed, and insulin sensitivity was calculated using Bergman's minimal model. Additional clinical assessments included anthropometry, body composition using whole-body X-ray absorptiometry (DXA) scans, clinic blood pressure, and 24-hour ambulatory blood pressure monitoring. RESULTS Children born very preterm were 0.69 SDS lighter (p<0.001), 0.53 SDS shorter (p=0.003), and had BMI 0.57 SDS lower (p=0.003) than children born at term.Notably, children born very preterm had insulin sensitivity that was 25% lower than term controls (9.4vs 12.6 x10-4 ·min-1 ·(mU/l); p=0.001).Other parameters of glucose metabolism, including fasting insulin levels, were similar in the two groups. The awake systolic blood pressure (from 24-hour monitoring) tended to be 3.1 mmHg higher on average in children born very preterm (p=0.054), while the clinic systolic blood pressure was 5.4 mmHg higher (p=0.002). CONCLUSIONS Lower insulin sensitivity remains a feature of children born very preterm, despite improvements in neonatal intensive care. As reported in our original study, our findings suggest the defect in insulin action in pre-pubertal children born very pretermis primarily peripheral and not hepatic. This article is protected by copyright. All rights reserved.