Friedman J F, Phillips-Howard P A, Mirel L B, Terlouw D J, Okello N, Vulule J M, Hawley W A, Nahlen B L, ter Kuile F
US Department of State, Institute of International Education, Fulbright Fellowships, Washington, DC, USA.
Eur J Clin Nutr. 2005 Aug;59(8):914-22. doi: 10.1038/sj.ejcn.1602161.
The objectives of this study were (1) to assess whether a cohort of school-aged children experiences progression of stunting over a 2-y-period of observation and (2) to identify baseline nutritional and body composition risk factors for the progression of stunting.
As part of a large-scale, randomized controlled trial assessing the impact of insecticide-treated bednets (ITNs) on nutritional status, we longitudinally followed a cohort of school-aged children over a 2-y-period in western Kenya. Anthropometric measurements were made at four time points from which Z-scores for height-for-age (HAZ), weight-for-age (WAZ), and body mass index (BMIZ) were calculated. Two measures of body composition, upper arm fat area and upper arm muscle area, were derived from mid-upper arm circumference (MUAC) and triceps skinfold thickness.
Subjects experienced a mean change in HAZ from baseline to 9 months of -0.16 [-0.19, -0.13], from baseline to 16 months of -0.18 [-0.22, -0.15], and from baseline to 24 months of -0.36 [-0.41, -0.31]. Thus, the average individual's change in HAZ at the three follow-up time points is significantly less than zero, meaning that, on average, the cohort is deviating further from NCHS reference medians over time. The baseline nutritional measure that explained the greatest amount of variance in the progression of stunting was the upper arm muscle area Z-score (F=8.1; P=0.005).
This longitudinal study provides further evidence from a distinct ecological setting regarding the progression of undernutrition during middle childhood in the developing world. It suggests that school-aged children in the developing world do not experience catch-up growth or remain stable. Rather, they continue to deviate from NCHS standards, accruing greater height deficits with age. In addition, absolute lean body mass explained the most variability in the progression of stunting, which supports cross-sectional findings from other studies.
本研究的目的是：（1）评估一组学龄儿童在2年观察期内发育迟缓是否会进展；（2）确定发育迟缓进展的基线营养和身体成分风险因素。
作为一项评估经杀虫剂处理的蚊帐（ITN）对营养状况影响的大规模随机对照试验的一部分，我们在肯尼亚西部对一组学龄儿童进行了为期2年的纵向跟踪。在四个时间点进行人体测量，并计算年龄别身高（HAZ）、年龄别体重（WAZ）和体重指数（BMIZ）的Z评分。从肱三头肌皮褶厚度和上臂中部周长（MUAC）得出两项身体成分指标，即上臂脂肪面积和上臂肌肉面积。
从基线到9个月，受试者的HAZ平均变化为-0.16[-0.19，-0.13]；从基线到16个月，为-0.18[-0.22，-0.15]；从基线到24个月，为-0.36[-0.41，-0.31]。因此，在三个随访时间点，个体HAZ的平均变化显著小于零，这意味着，随着时间的推移，该队列平均而言越来越偏离美国国家卫生统计中心（NCHS）的参考中位数。解释发育迟缓进展中最大方差量的基线营养指标是上臂肌肉面积Z评分（F=8.1；P=0.005）。
这项纵向研究在一个独特的生态环境中提供了关于发展中国家童年中期营养不良进展的进一步证据。研究表明，发展中国家的学龄儿童不会出现追赶生长或保持稳定。相反，他们继续偏离NCHS标准，随着年龄增长身高赤字更大。此外，绝对瘦体重在发育迟缓进展中解释的变异性最大，这支持了其他研究的横断面研究结果。
