Relationship between catch-up growth of premature infants and insulin resistance / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the effect of catch-up growth on insulin resistance(IR) through analysis of biochemical and metabolic indices in premature infants.Methods There were 126 infants admitted in the Department of Neonatology,the Affiliated Hospital of Guiyang Medical College from December 2010 to December 2013 [factors which might affect the secretion of insulin(INS),C peptide and insulin-like growth factor-1 (IGF-1) were excluded].According to gestational age and birth weight,babies were divided into small for gestational age (SGA) group and appropriate for gestational age (AGA) group.And according to the age on follow-up,babies were divided into 1-to-6-month-old group,7-to-12-month-old group and ≥ 1-to-3 year-old group.All cases had 6 mL peripheral venous blood sampled in the early morning during fasting in the first week,and 6,12,24,36 months after birth.They were tested for levels of INS,C peptide,IGF-1,triglyceride (TC),total cholesterol (TG),high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C),fasting blood-glucose (FBG),albumin,prealbumin and creatinine respectively.At the same time,the physical parameters were measured,including weight,body length,and calculated insulin resistance index (IRI),Ponderal index,weight standard deviation score (SDS),and length SDS.Results (1) Catch-up growth after premature birth occupied 65.6％ (63/96 cases),whereas no catch-up growth occupied 34.4％ (33/96 cases) of study snbjects,and among them catch-up growth of 37 cases was better (8 cases of SGA,29 cases of AGA),26 cases showing catch-up growth(7 cases of SGA,19 cases of AGA),33 cases without catch-up growth(11 cases of SGA,22 cases of AGA).No statistical significance was found in the distribution of catch-up growth between SGA group and AGA group(P ＞ 0.05).(2) The LgIRI,LgINS of group with good catch-up growth was significantly lower than the group with no catch-up growth group (F =3.55,3.47) in infancy,but the level of IGF-1 and prealbumin was higher than that of no catch-up growth group (F =3.55,4.94),the difference had statistical significance (P ＜ 0.05) ; the better catch-up growth was associated with higher IGF-1 and prealbumin,but with lower LgIRI.(3) The risk factors for insulin resistance were SGA (OR =7.904,P =0.001),low birth weight ＜ 1 500 g (OR=8.737,P=0.019),and no catch-up growth (OR=11.706,P=0.000).Conclusions The better catch-up growth in infancy is associated with higher IGF-1 and prealbumin,but lower IR.The risk factors of IR include SGA,low birth weight and no catch-up growth,and the last being the major factor.