Insulin resistance in pre-school very-low-birth weight pre-term children

AIMS: To evaluate the metabolic pattern of a group of pre-school small- (SGA) and appropriate-for-gestational age (AGA) pre-term very-low-birthweight (VLBW) (<1500 gr) Italian children and retrospectively verify if the growth rate in the first years of life is associated to the laboratory and anthropometric characteristics of these children. METHODS: 58 (16 SGA, 42 AGA) VLBW children, without major congenital malformations/conditions were enrolled; their anthropometric, clinical and (in 34 of them) laboratory characteristics were evaluated at pre-school age (> 2<6 years of corrected age). RESULTS: Clinical, anthropometric and laboratory characteristics at pre-school age were similar in SGA and AGA. Sixty-nine percent of SGA and 51% of AGA children showed a significant weight centile crossing (CC) at 24 months. Fasting serum glucose, insulin and insulin resistance (evaluated by the Homeostasis Model Assessment -HOMA-IR-) were higher in AGA and SGA with CC. The increment in weight standard deviation scores from birth-to-24 months was significantly associated with pre-school BMI SDS, waist, fasting insulin, and HOMA-IR values, both in unadjusted and adjusted models. In a multiple regression model, after multiple adjustments, this increment is the only significant predictor of pre-school insulin (B = 0.19; 95%CI 0.07-0.31; P = 0.006) and HOMA-IR levels (B = 0.20; 95%CI 0.08-0.32; P = 0.004) both in SGA and AGA children. CONCLUSIONS: The adverse metabolic pattern of pre-school VLBW children seems related to post-natal events (rapid weight growth) independently by their being small- or appropriate-for gestational age.