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

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.

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).

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.

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.