Premature birth and insulin resistance in infancy: A prospective cohort study

OBJECTIVE: This study was done to determine the role of prematurity and other variables to predict insulin sensitivity in infancy. SUBJECTS AND METHODS: In this prospective study, 36 preterm appropriate for gestational age (AGA), 11 preterm small for gestational age (SGA), and 17 term SGA included as study cohort and 36 term AGA as control cohort. Detailed anthropometry assessment was performed at birth, 3, 6, and 9 months and at 9 months, fasting plasma glucose and serum insulin was done. Insulin resistance was determined by using homeostasis model assessment version 2. RESULTS: It is found that preterm AGA (mean difference 0.617, 95% confidence interval [CI]; 0.43–0.80, P = 0.0001), preterm SGA (mean difference 0.764, 95% CI; 0.44–1.09, P = 0.0001), and term AGA (mean difference 0.725, 95% CI; 0.49–0.96, P = 0.0001) group had significantly higher insulin resistance than control. There was no significant difference in between preterm SGA and preterm AGA (mean difference 0.147 95% CI; −0.13–0.42, P = 0.927). In multiple regression models, SGA status (β =0.505) was more significant predictor of insulin resistance index than gestational age (β = −0.481), weight-for-length (β =0.315), and ponderal index (β = −0.194). CONCLUSION: Preterm birth is a risk factor for the future development of insulin resistance which may develop as early as infancy.