Incidence of extrauterine growth retardation and associated factors in very low birth weight preterm infants / 中华围产医学杂志

ABSTRACT

Objective To assess the incidence of extrauterine growth retardation (EUGR) in very low birth weight (VLBW) preterm infants and to evaluate the effects of nutritional support and morbidities on EUGR.Methods Data of VLBW preterm infants ＜ 34 weeks of gestation admitted to the Neonatal Intensive Care Unit (NICU) of the First Affiliated Hospital of Sun Yat-Sen University between January 1,2005 and December 31,2010 were reviewed.Those VLBW preterm infants were divided into the EUGR group (n=67) and the non-EUGR group (n=40).Perinatal data,growth data,nutritional information and morbidities were compared between the two groups.The incidence of EUGR in VLBW preterm infants was assessed and the associated risk factors were analyzed.Independent samples t,Chi-square and rank sum tests and Logistic regression analysis were used for statistical analyses.Results A total of 107 VLBW infants survived to discharge.The average gestational age in the EUGR group was much lower than that in the non-EUGR group [(30.0±2.1) weeks vs (30.9 ± 1.1) weeks,t=2.904,P=0.002].However,the incidences of small for gestational age (SGA) and maternal hypertension in the EUGR group was higher than that in the non-EUGR group [SGA53.7％ (36/67) vs 15.0％ (6/40),x2=15.575,P ＜ 0.01; maternal hypertension40.3％ (27/67) vs 20.0％ (8/40),x2=4.689,P=0.030].Standard deviation score (SDS) of birth weight and weight at discharge in the EUGR group was lower than that in the non-EUGR group [SDS of birth weight(--1.9±0.8) vs (--1.1±0.7),t=5.418; weight at discharge-2.6 (-3.0--2.0) vs-0.5 (-0.9--0.1),U=30.271; both P ＜ 0.01].The velocity of weight gain in the EUGR group was lower than that in the non-EUGR group [(12.0±4.4) g/(kg · d) vs (16.1±4.0) g/(kg · d),t=1.879,P=0.036],while the maximum percentage of weight loss and the age at maximum weight loss in the EUGR group was higher than that in the non-EUGR group [percentage of weight loss(13.2± 1.7)％ vs (9.0± 1.6)％,t=12.832,P ＜ 0.01; age(13.4±3.5) vs (10.9±4.3) d,t=3.113,P=0.001].The time to achieve full enteral feeds,3 g/(kg · d) protein and 120 kcal/(kg · d) calories intake were longer in than the EUGR group [(39.7 ± 8.2) vs (30.8±6.1) d,t=6.293,P=0.007; (21.4±5.8) vs (17.5±1.3) d,t=4.286,P=0.002; (28.4±6.0) vs (20.3±5.4) d,t=7.198,P=0.015; 1 kcal=4.184 k J].The cumulative caloric deficit and cumulative protein deficit in the first two weeks of life in the EUGR group were significantly higher than those in the non-EUGR group [(600.9±49.3) vs (536.4 ± 55.2) kcal/kg,t=6.082,P ＜ 0.01; (17.4 ± 0.8) vs (12.4 ± 0.8) g/kg,t=31.279,P=0.003,respectively].The incidences of late-onset infection and bronchopulmonary dysplasia (BPD) in the EUGR group was significantly higher than that in the non-EUGR group [77.6％ (52/67) vs 40.0％ (16/40),x2=15.300,P ＜ 0.01;38.8％ (26/67) vs 17.5％ (7/40),x2=5.330,P=0.040,respectively].The length of oxygen therapy and mechanical ventilation in the EUGR group were significantly longer than that in the non-EUGR group [(44.5 ±4.5) vs (32.5± 1.5) d,t=20.042,P=0.030; 9.5(6.5-44.0) d vs 6.2(5.0-35.5) d,U=19.195,P=0.004,respectively].Logistic regression analysis showed that SGA,gestational age,BPD,late-onset infection,time to achieve full enteral feeds and 3 g/(kg · d) protein intake and the cumulative caloric deficit in the first two weeks after birth were the independent risk factors for EUGR (all P ＜ 0.05).Conclusions EUGR remains a serious issue in VLBW preterm infants,especially SGA,in the NICU.An early aggressive nutritional strategy,prevention of BPD and infection,and improvement of perinatal care may facilitate a reduction in the occurrence of EUGR.