老年阿尔茨海默病患者肠道微生态改变及其与认知功能的关系探讨

Correlation between intestinal microecological changes and cognitive function in elderly patients with Alzheimer′s disease

目的探讨老年阿尔茨海默症患者肠道微生态结构与认知功能的关系。方法将2016年7月-2019年5月医院收治的86例老年阿尔茨海默病患者和73例健康志愿者,分别记为研究组和对照组。采用简易精神状态评价量表(MMSE)进行评分评价两组认知功能,采用高通量测序检测两组肠道微生物多样性。比较两组肠道微生物多样性与MMSE评分,并比较研究组中认知功能正常者与障碍者肠道微生物结构;采用Pearson相关性分析法探讨肠道微生物结构与认知功能障碍者的相关性。结果研究组肠道菌群Chao1指数、Shannon指数、放线菌门、拟杆菌门、放线菌科、乳杆菌科、拟杆菌科、双歧杆菌属、乳杆菌属、拟杆菌属、MMSE评分均低于对照组(均P<0.05);研究组厚壁菌门、变形菌门、子囊菌门、梭菌科、假单胞菌科、葡萄球菌科、肠杆菌科、隐球酵母科、梭状芽孢杆菌属、假单胞菌属、葡萄球菌属、变形杆菌属、假丝酵母菌属相对丰度均高于对照组(均P<0.05);研究组中认知功能障碍发生率为70.93%,且认知功能障碍者肠道菌群Chao1指数、Shannon指数,门、科、属水平相对丰度与认知功能正常者对比和上述结果一致;研究组与对照组肠道拟杆菌门、子囊菌门、拟杆菌科、梭状芽胞杆菌属、假丝酵母菌属、放线菌门、乳杆菌属、拟杆菌属相对丰度差异具有统计学意义(均P<0.05);研究组认知功能障碍与认知功能正常者肠道未分类拟杆菌门、子囊菌门、假单胞菌属、拟杆菌属、变形杆菌属、梭状芽孢杆菌属、拟杆菌门、拟杆菌科、假丝酵母菌属相对丰度差异具有统计学意义(均P<0.05);研究组中肠道菌群Chao1指数、Shannon指数,放线菌门、拟杆菌门、放线菌科、乳杆菌科、拟杆菌科、双歧杆菌属、乳杆菌属、拟杆菌属相对丰度与MMSE评分均呈正相关,厚壁菌门、变形菌门、子囊菌门、梭菌科、假单胞菌科、葡萄球菌科、肠杆菌科、隐球酵母科、梭状芽孢杆菌属、假单胞菌属、葡萄球菌属、变形杆菌属、假丝酵母菌属相对丰度与MMSE评分均呈负相关。结论老年阿尔茨海默病患者肠道微生物结构存在异常,且认知功能障碍者更加严重,认知功能与肠道微生物相关。

Objective To observe the correlation between intestinal microecology and cognitive function in elderly patients with Alzheimer′s disease(AD). Methods Eighty-six elderly patients with AD admitted into the hospital from July 2016 to May 2019 and 73 healthy volunteers were divided into observation group and control group respectively. High throughput sequencing was used to detect the intestinal microbial diversity, and MMSE was used to evaluate the cognitive function. The intestinal microbial diversity and MMSE scores were compared between groups. In the observation group, the intestinal microbial structure was compared between those with normal cognitive function and those with impairment. The relationship between intestinal microbial structure and cognitive impairment was explored using Pearson correlation analysis. Results The Chao1 index, Shannon index and relative abundances of intestinal microbes in the observation group were significantly different than those in the control group, respectively(all P<0.05). The incidence of cognitive dysfunction in the observation group was 70.93%, and the Chao1 indexes, Shannon indexes and the relative abundances of microbes in patients with cognitive dysfunction were significantly different from those without. In the observation group, the Chao1 index, Shannon index and relative abundances of Actinobacteria, Bacteroidetes, Actinomycetaceae, Lactobacillaceae, Bacteroidaceae, Bifidobacterium, Lactobacillus and Bacteroides were positively related to the MMSE score, while the relative abundances of Firmicutes, Proteobacteria, Ascomycota, Clostridiaceae, Pseudomonaceae, Staphylococcaceae, Enterobacteriaceae, Cryptococcgeniusae, Clostridium, Pseudomonas, Staphylococcus, Proteus and Candida were negatively related to the MMSE score. Conclusion There are serious abnormalities in the structure of intestinal microflora in the elderly patients with Alzheimer′s disease. The cognitive function is positively correlated with the diversity of intestinal microflora, and also with the relative abundances of intestinal microflora at the levels of phylum, family and genus.