Hosseini Sayed-Mohsen, Maracy Mohamad-Reza, Sarrafzade Sheida, Kelishadi Roya
Department of Bio-statistics and Epidemiology, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Pediatrics, Faculty of Medicine and Child Growth and Development Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
Int J Prev Med. 2014 Mar;5(3):348-55.
Growth is one of the most important indices in child health. The best and most effective way to investigate child health is measuring the physical growth indices such as weight, height and head circumference. Among these measures, weight growth is the simplest and the most effective way to determine child growth status. Weight trend at a given age is the result of cumulative growth experience, whereas growth velocity represents what is happening at the time.
This longitudinal study was conducted among 606 children repeatedly measured from birth until 2 years of age. We used linear mixed model to analyze repeated measures and to determine factors affecting the growth trajectory. LOWESS smooth curve was used to draw velocity curves.
Gender, child rank, birth status and feeding mode had a significant effect on weight trajectory. Boys had higher weight during the study. Infants with exclusive breast feeding had higher weight than other infants. Boys had higher growth velocity up to age 6 month. Breast fed infants had higher growth velocity up to 6 month, but thereafter the velocity was higher in other infants.
Many of the studies have investigated child growth, but most of them used cross-sectional design. In this study, we used longitudinal method to determine effective factors on weight trend in children from birth until 2-year-old. The effects of perinatal factors on further growth should be considered for prevention of growth disorders and their late complications.
生长是儿童健康最重要的指标之一。调查儿童健康的最佳且最有效的方法是测量诸如体重、身高和头围等身体生长指标。在这些测量指标中，体重增长是确定儿童生长状况最简单且最有效的方法。特定年龄的体重趋势是累积生长经历的结果，而生长速度则反映当时的生长情况。
这项纵向研究对606名从出生到2岁被反复测量的儿童进行。我们使用线性混合模型分析重复测量数据并确定影响生长轨迹的因素。采用局部加权散点平滑法（LOWESS）绘制速度曲线。
性别、孩子排行、出生状况和喂养方式对体重轨迹有显著影响。在研究期间男孩体重更高。纯母乳喂养的婴儿比其他婴儿体重更高。男孩在6个月龄前生长速度更快。母乳喂养的婴儿在6个月龄前生长速度更快，但此后其他婴儿的生长速度更高。
许多研究都对儿童生长进行了调查，但大多数采用的是横断面设计。在本研究中，我们使用纵向方法来确定从出生到2岁儿童体重趋势的影响因素。为预防生长障碍及其后期并发症，应考虑围产期因素对后续生长的影响。
