Ong Ken K, Langkamp Markus, Ranke Michael B, Whitehead Karen, Hughes Ieuan A, Acerini Carlo L, Dunger David B
Medical Research Council Epidemiology Unit, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK.
Am J Clin Nutr. 2009 Jul;90(1):156-61. doi: 10.3945/ajcn.2008.27408. Epub 2009 May 27.
Formula milk-fed infants show faster rates of growth and weight gain than do breastfed infants, and they have higher concentrations of insulin-like growth factor I (IGF-I).
Our objective was to determine the influence of IGF-I concentrations on gains in weight, length, body mass index (BMI), and adiposity in the first year of life.
IGF-I concentrations were measured in 953 capillary blood samples from 675 unselected infants at ages 3 and 12 mo. These infants were born between 2002 and 2008 in one center and were participating in a prospective longitudinal birth cohort. Weight, length, and 4 skinfold thicknesses as an indicator of adiposity were measured at ages 0, 3, and 12 mo. Analyses were adjusted for age and sex.
Infants who were formula milk-fed had higher IGF-I concentrations at 3 mo, and they showed greater gains in weight, length, BMI, and adiposity between age 3 and 12 mo. IGF-I concentrations at 3 mo were unrelated to subsequent overall weight gain (P = 0.5). However, higher IGF-I concentrations at age 3 mo predicted greater subsequent gains in body length (P < 0.001 and P = 0.007 in formula milk-fed and breastfed infants, respectively) and slower gains in BMI (P < 0.001 and P = 0.004, respectively) and adiposity (P = 0.03 and P = 0.003, respectively).
Our findings support a key role for IGF-I in the partitioning of overall infant weight gain into statural growth compared with adiposity. In formula milk-fed infants, higher IGF-I concentrations may lead to faster gains in length; however, other mechanisms likely explain their faster gains in weight, BMI, and adiposity.
配方奶喂养的婴儿比母乳喂养的婴儿生长速度更快、体重增加更多，且胰岛素样生长因子I（IGF-I）浓度更高。
我们的目的是确定IGF-I浓度对生命第一年体重、身长、体重指数（BMI）和肥胖程度增加的影响。
对675名未经过筛选的婴儿在3个月和12个月大时采集的953份毛细血管血样中的IGF-I浓度进行了测量。这些婴儿于2002年至2008年在一个中心出生，并且参与了一项前瞻性纵向出生队列研究。在0、3和12个月大时测量了体重、身长以及作为肥胖程度指标的4个皮褶厚度。分析针对年龄和性别进行了校正。
配方奶喂养的婴儿在3个月时IGF-I浓度更高，并且在3至12个月龄之间体重、身长、BMI和肥胖程度增加更多。3个月时的IGF-I浓度与随后的总体体重增加无关（P = 0.5）。然而，3个月龄时较高的IGF-I浓度预示着随后身长增加更多（配方奶喂养和母乳喂养的婴儿分别为P < 0.001和P = 0.007）以及BMI（分别为P < 0.001和P = 0.004）和肥胖程度（分别为P = 0.03和P = 0.003）增加较慢。
我们的数据支持IGF-I在将婴儿总体体重增加分配到身高生长而非肥胖方面起关键作用。在配方奶喂养的婴儿中，较高的IGF-I浓度可能导致身长增加更快；然而，其他机制可能解释了他们在体重、BMI和肥胖程度方面增加更快的原因。
