使用高通量测序技术可以更准确地研究肥胖中的肠道微生物组是否在门或属水平上具有较低的多样性和改变的组成。我们在PubMed和Embase中进行了系统评价,包括32项横断面研究,通过高通量测序评估肥胖和非肥胖成年人的肠道微生物组组成。在22项研究中,有9项观察到肥胖成年人与非肥胖成年人的α多样性(香农指数)明显降低。和7项研究的荟萃分析显示平均差异不显著(-0.06,95%CI-0.24,0.12,I2=81%).在门一级,与非肥胖成年人相比,肥胖成年人中的17人中有6人观察到更多的Firmicutes和更少的拟杆菌,在18项研究中的4项,分别。六项研究的荟萃分析显示,Firmicutes明显较高(5.50,95%0.27,10.73,I2=81%),而拟杆菌则不明显较低(-4.79,95%CI-10.77,1.20,I2=86%)。在属一级,相对比例较低的双歧杆菌和Eggerthella和更高的酸性球菌,缺氧球菌,副杆菌属,Dialister,Dorea,大肠杆菌志贺氏菌,真细菌,梭杆菌,Megasphera,普雷沃氏菌,罗斯布里亚,链球菌,在肥胖和非肥胖的成年人中发现了Sutterilla。尽管有部分研究发现肥胖和非肥胖成年人的肠道微生物组组成多样性和差异较低,观察到的不同研究的异质性排除了明确的答案.
Whether the gut microbiome in obesity is characterized by lower diversity and altered composition at the phylum or genus level may be more accurately investigated using high-throughput sequencing technologies. We conducted a systematic
review in PubMed and Embase including 32 cross-sectional studies assessing the gut microbiome composition by high-throughput sequencing in obese and non-obese adults. A significantly lower alpha diversity (Shannon index) in obese versus non-obese adults was observed in nine out of 22 studies, and meta-analysis of seven studies revealed a non-significant mean difference (-0.06, 95% CI -0.24, 0.12, I2 = 81%). At the phylum level, significantly more Firmicutes and fewer Bacteroidetes in obese versus non-obese adults were observed in six out of seventeen, and in four out of eighteen studies, respectively. Meta-analyses of six studies revealed significantly higher Firmicutes (5.50, 95% 0.27, 10.73, I2 = 81%) and non-significantly lower Bacteroidetes (-4.79, 95% CI -10.77, 1.20, I2 = 86%). At the genus level, lower relative proportions of Bifidobacterium and Eggerthella and higher Acidaminococcus, Anaerococcus, Catenibacterium, Dialister, Dorea, Escherichia-Shigella, Eubacterium, Fusobacterium, Megasphera, Prevotella, Roseburia, Streptococcus, and Sutterella were found in obese versus non-obese adults. Although a proportion of studies found lower diversity and differences in gut microbiome composition in obese versus non-obese adults, the observed heterogeneity across studies precludes clear answers.