Department of Epidemiology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD, USA.
Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
BMC Microbiol. 2020 Mar 11;20(1):56. doi: 10.1186/s12866-020-01723-9.
Early introduction of complementary foods has been associated with various immune disorders, oxidative stress, and obesity in childhood. The gut microbiota and the short chain fatty acids (SCFAs) they produce are postulated to be on the causal pathway. The objective of this study was to determine if early complementary feeding (i.e. consumption of solids or non-water/formula liquids at or before 3 months) is prospectively associated with infant gut microbiota composition, diversity and SCFAs at 3 and 12 months of age in the Nurture birth cohort.
Mother-infant dyads in the early complementary feeding group (n = 18) had similar baseline characteristics to those in the later feeding group (n = 49). We assessed differential abundance of microbial taxa (measured by 16S rRNA gene sequencing of the V4 region) by timing of complementary feeding using beta-binomial regression models (considering a two-sided FDR corrected p-value of < 0.05 as significant), and we fittted linear regression models to assess the association between early complementary feeding and SCFA concentrations (quantified using gas chromatography). After multivariable adjustment for breastfeeding, delivery method, birth weight, and gestational age, there were 13 differentially abundant microbial amplicon sequence variants (ASVs) by timing of introduction to complementary foods at 3 months and 20 ASVs at 12 months. Infants introduced to complementary foods early (vs. later) had higher concentrations of the SCFA butyric acid (mean difference = 0.65, 95% CI: 0.27, 1.04, p < 0.01) and total SCFAs (mean difference = 38.8, 95% CI: 7.83, 69.7) at 12 months. Bilophila wadsworthia and Lachnospiraceae Roseburia were associated with early (vs. later) complementary feeding and with higher butyric acid concentrations at 3 and 12 months, respectively.
Our findings are consistent with the hypothesis that early (vs. later) introduction to complementary foods is associated with altered gut microbiota composition and butyric acid concentrations measured in stool until at least 1 year of age. Further research is needed to determine if these changes mediate future development of metabolic and immune conditions.
早期引入补充食品与儿童期的各种免疫紊乱、氧化应激和肥胖有关。肠道微生物群及其产生的短链脂肪酸（SCFAs）被认为处于因果途径上。本研究的目的是确定早期补充喂养（即在 3 个月或之前食用固体或非水/配方液体）是否与 Nurture 出生队列中 3 个月和 12 个月时婴儿肠道微生物群组成、多样性和 SCFAs 有前瞻性关联。
早期补充喂养组（n=18）的母婴对与后期喂养组（n=49）的基线特征相似。我们通过补充喂养的时间使用 beta-binomial 回归模型（考虑双侧 FDR 校正 p 值 <0.05 为显著）来评估微生物分类群的差异丰度（通过 16S rRNA 基因测序 V4 区测量），并使用线性回归模型评估早期补充喂养与 SCFA 浓度之间的关系（使用气相色谱法定量）。在对母乳喂养、分娩方式、出生体重和胎龄进行多变量调整后，在 3 个月时引入补充食物的时间有 13 个微生物扩增序列变异（ASV）差异丰富，在 12 个月时有 20 个 ASV 差异丰富。与较晚引入补充食物相比，早期（vs. 较晚）引入补充食物的婴儿在 12 个月时丁酸（平均差异=0.65，95%CI：0.27，1.04，p<0.01）和总 SCFA（平均差异=38.8，95%CI：7.83，69.7）的浓度更高。Bilophila wadsworthia 和 Lachnospiraceae Roseburia 与早期（vs. 较晚）补充喂养相关，与 3 个月和 12 个月时丁酸浓度更高相关。
我们的研究结果与以下假设一致，即与较晚（vs. 较早）引入补充食物相比，早期（vs. 较晚）引入补充食物与粪便中至少 1 岁时的肠道微生物群组成和丁酸浓度的改变有关。需要进一步研究以确定这些变化是否介导未来代谢和免疫状况的发展。
