Background

Stunting is the most prevalent manifestation of childhood malnutrition. To characterize factors that contribute to stunting in resource-poor settings, we studied a priori selected biological and social factors collected longitudinally in a cohort of newborns.

Methods and findings

We enrolled 1,868 children across 7 resource-poor settings in Bangladesh, Brazil, India, Nepal, Peru, South Africa, and Tanzania shortly after birth and followed them for 24 months between 2 November 2009 and 28 February 2014. We collected longitudinal anthropometry, sociodemographic factors, maternal-reported illnesses, and antibiotic use; child feeding practices; dietary intake starting at 9 months; and longitudinal blood, urine, and stool samples to investigate non-diarrheal enteropathogens, micronutrients, gut inflammation and permeability, and systemic inflammation. We categorized length-for-age Z-scores into 3 groups (not stunted, ≥−1; at risk, <−1 to −2; and stunted, <−2), and used multivariable ordinal logistic regression to model the cumulative odds of being in a lower length-for-age category (at risk or stunted). A total of 1,197 children with complete longitudinal data were available for analysis. The prevalence of having a length-for-age Z-score below −1 increased from 43% (range 37%–47% across sites) shortly after birth (mean 7.7 days post-delivery, range 0 to 17 days) to 74% (16%–96%) at 24 months. The prevalence of stunting increased 3-fold during this same time period. Factors that contributed to the odds of being in a lower length-for-age category at 24 months were lower enrollment weight-for-age (interquartile cumulative odds ratio = 1.82, 95% CI 1.49–2.23), shorter maternal height (2.38, 1.89–3.01), higher number of enteropathogens in non-diarrheal stools (1.36, 1.07–1.73), lower socioeconomic status (1.75, 1.20–2.55), and lower percent of energy from protein (1.39, 1.13–1.72). Site-specific analyses suggest that reported associations were similar across settings. While loss to follow-up and missing data are inevitable, some study sites had greater loss to follow-up and more missing data than others, which may limit the generalizability of the findings.

Conclusions

Neonatal and maternal factors were early determinants of lower length-for-age, and their contribution remained important throughout the first 24 months of life, whereas the average number of enteropathogens in non-diarrheal stools, socioeconomic status, and dietary intake became increasingly important contributors by 24 months relative to neonatal and maternal factors.

中文翻译：

---

儿童期发育迟缓与生命前两年的产前和产后环境相关：MAL-ED 纵向出生队列研究

背景

发育迟缓是儿童营养不良最普遍的表现。为了描述资源匮乏环境中导致发育迟缓的因素，我们研究了在新生儿队列中纵向收集的先验选定的生物和社会因素。

方法和结果

我们在孟加拉国、巴西、印度、尼泊尔、秘鲁、南非和坦桑尼亚的 7 个资源匮乏地区招募了 1,868 名出生后不久的儿童，并在 2009 年 11 月 2 日至 2014 年 2 月 28 日期间对他们进行了为期 24 个月的跟踪调查。我们收集了纵向人体测量学、社会人口学数据因素、孕产妇报告的疾病和抗生素的使用；儿童喂养习惯；9个月时开始饮食摄入；以及纵向血液、尿液和粪便样本，以研究非腹泻性肠道病原体、微量营养素、肠道炎症和通透性以及全身炎症。我们将年龄别身长Z分数分为 3 组（未发育迟缓，≥−1；有风险，<−1 至 −2；发育迟缓，<−2），并使用多变量序数逻辑回归对累积赔率进行建​​模属于年龄别身高较低的类别（有风险或发育迟缓）。共有 1,197 名具有完整纵向数据的儿童可供分析。出生后不久（平均产后 7.7 天，范围 0 至 17 天），年龄别身长Z值低于 -1 的患病率从 43%（各地范围为 37%–47%）增加到 74% 24 个月时 (16%–96%)。同一时期，发育迟缓的发生率增加了 3 倍。导致 24 个月时处于较低年龄别身长类别的可能性的因素包括入组年龄别体重较低（四分位数累积比值比 = 1.82，95% CI 1.49–2.23）、母亲身高较短（2.38， 1.89–3.01），非腹泻粪便中肠道病原体数量较多（1.36，1.07–1.73），社会经济地位较低（1.75，1.20–2.55），蛋白质能量百分比较低（1.39，1.13–1.72）。特定地点的分析表明，报告的关联在不同环境中是相似的。虽然失访和数据缺失是不可避免的，但一些研究中心的失访和数据缺失比其他研究中心更大，这可能会限制研究结果的普遍性。

结论

新生儿和母亲因素是较低年龄别身长的早期决定因素，在生命的前 24 个月中，它们的贡献仍然很重要，而非腹泻粪便中肠道病原体的平均数量、社会经济状况和饮食摄入量则成为越来越重要的影响因素相对于新生儿和孕产妇因素，延长了 24 个月。