Food and Human Nutrition Research Group, Universidad de Antioquia (UdeA), Medellín, Antioquia, Colombia.
INSERM UMR S-1139 3PHM, Université Paris Cité, 75006, Paris, France.
BMC Geriatr. 2022 Apr 28;22(1):373. doi: 10.1186/s12877-022-02981-0.
Aging generates changes in the gut microbiota, affecting its functionality. Little is known about gut microbiota in critically ill older adults. The objective of this study was to describe the profile of gut microbiota in a cohort of critically ill older adults.
This observational study was conducted in five health institutions. Over a 6-month study period, critically ill patients over 18 years old who were admitted to the intensive care unit were enrolled. Fecal microbiota profiles were determined from 155 individuals, over 60 years old (n = 72) and under 60 years old (n = 83). Gut microbiota was analyzed by sequencing the V3-V4 region of the 16S rRNA gene. Alpha and beta diversity, operational taxonomic units and the interaction of gut microbiota with variables under study were analyzed. Amplicon sequence variants (ASVs) specifically associated with age were recovered by including gender, discharge condition, BMI, ICU stay and antibiotics as covariates in a linear mixed model.
In older adults, sepsis, malnutrition, antibiotic prescription and severity (APACHE and SOFA scores) were higher than in the group under 60 years of age. Alpha diversity showed lower gut microbiota diversity in those over 60 years of age (p < 0.05); beta diversity evidenced significant differences between the groups (PERMANOVA = 1.19, p = 0.038). The microbiota of the adults under 60 years old showed greater abundance of Murdochiella, Megasphaera, Peptoniphilus and Ezakiella, whereas those over 60 years old Escherichia-Shigella and Hungatella were more abundant.
The gut microbial community was altered by different factors; however, age significantly explained the variability in critically ill patients. A lower presence of beneficial genera and a higher abundance of pathogens was observed in adults over 60 years old.
衰老会导致肠道微生物群发生变化，从而影响其功能。目前对于危重症老年患者的肠道微生物群知之甚少。本研究旨在描述危重症老年患者肠道微生物群的特征。
这是一项观察性研究，在五家医疗机构进行。在 6 个月的研究期间，收入了年龄在 18 岁以上、入住重症监护病房的危重症患者。从 155 名年龄在 60 岁以上（n=72）和 60 岁以下（n=83）的个体中确定了粪便微生物群的特征。通过对 16S rRNA 基因的 V3-V4 区进行测序来分析肠道微生物群。分析了 alpha 和 beta 多样性、操作分类单位以及肠道微生物群与研究变量的相互作用。通过在线性混合模型中纳入性别、出院情况、BMI、入住 ICU 时间和抗生素作为协变量，回收与年龄特异性相关的扩增子序列变异（ASV）。
在老年患者中，脓毒症、营养不良、抗生素处方和严重程度（APACHE 和 SOFA 评分）高于 60 岁以下患者。60 岁以上患者的 alpha 多样性显示肠道微生物多样性较低（p<0.05）；beta 多样性两组间有显著差异（PERMANOVA=1.19，p=0.038）。60 岁以下成年人的微生物群中 Murdochiella、Megasphaera、Peptoniphilus 和 Ezakiella 的丰度较高，而 60 岁以上患者中 Escherichia-Shigella 和 Hungatella 的丰度较高。
不同因素改变了肠道微生物群落；然而，年龄显著解释了危重症患者的变异性。在 60 岁以上成年人中，有益属的存在减少，而病原体的丰度增加。
