Children who were born post-term experienced insulin resistance, particularly boys who had additional features of metabolic syndrome. Researchers speculate that this insulin resistance is a preface to obesity, according to their data presented at The Endocrine Society’s 94th Annual Meeting and Expo.
Ahila Ayyavoo, MBBS, clinical research fellow at the University of Auckland in New Zealand, and colleagues sought to prove that prepubertal children born post-term display features of metabolic syndrome.
The study included two groups of prepubertal children aged 4 to 11 years. The post-term group (n=36) were born after 42 weeks of gestation, and the control group (n=56) were born at 38 to 40 weeks.
Data for boys and girls were studied separately. After an overnight fast, researchers conducted a frequently sampled IV glucose tolerance test with insulin. They studied biochemical markers of metabolic syndrome and used Bergman’s minimal model for calculating insulin sensitivity. Besides the overnight fast, they examined the children’s blood pressure during a 24-hour period.
According to data, insulin sensitivity was reduced in post-term boys (n=18; P=.014) and girls (n=18; P=.046) compared with the control group. Although there was an increase in acute insulin response in post-term boys (P=.009), there was no increase in post-term girls (P=.65). Additionally, insulin-like growth factor I was found to be lower in post-term boys (P=.027) and girls (P=.08). Further evidence suggested metabolic syndrome in post-term boys, as indicated by elevated IGF-III (P=.027) and a decrease in nocturnal systolic BP (P<.0001) and nocturnal diastolic BP (P<.004).
Dyslipidemia was reported in post-term boys, with higher total cholesterol (P=.058), LDL (P=.069) and triglycerides (P=.088) vs. boys who were born at 38 to 40 weeks, the researchers wrote.
Moreover, post-term boys displayed higher serum leptin (P=.056), regardless of similar body composition of boys born at 38 to 40 weeks (P=.47).
For more information:
Ayyavoo A. Abstract #OR09-6. Presented at: the Endocrine Society’s 94th Annual Meeting & Expo; June 23-26, 2012; Houston.
Disclosure: The researchers report no relevant financial disclosures.