title: Composition, variability, and temporal stability of the intestinal microbiota of the elderly.
abstract: Alterations in the human intestinal microbiota are linked to conditions including inflammatory bowel disease, irritable bowel syndrome, and obesity. The microbiota also undergoes substantial changes at the extremes of life, in infants and older people, the ramifications of which are still being explored. We applied pyrosequencing of over 40,000 16S rRNA gene V4 region amplicons per subject to characterize the fecal microbiota in 161 subjects aged 65 y and older and 9 younger control subjects. The microbiota of each individual subject constituted a unique profile that was separable from all others. In 68% of the individuals, the microbiota was dominated by phylum Bacteroides, with an average proportion of 57% across all 161 baseline samples. Phylum Firmicutes had an average proportion of 40%. The proportions of some phyla and genera associated with disease or health also varied dramatically, including Proteobacteria, Actinobacteria, and Faecalibacteria. The core microbiota of elderly subjects was distinct from that previously established for younger adults, with a greater proportion of Bacteroides spp. and distinct abundance patterns of Clostridium groups. Analyses of 26 fecal microbiota datasets from 3-month follow-up samples indicated that in 85% of the subjects, the microbiota composition was more like the corresponding time-0 sample than any other dataset. We conclude that the fecal microbiota of the elderly shows temporal stability over limited time in the majority of subjects but is characterized by unusual phylum proportions and extreme variability.
authors.affiliation: Department of Microbiology, University College, Cork, Ireland.
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Claesson
authors.forename: Siobhán
authors.initials: S
authors.lastname: Cusack
authors.forename: Orla
authors.initials: O
authors.lastname: O'Sullivan
authors.forename: Rachel
authors.initials: R
authors.lastname: Greene-Diniz
authors.forename: Heleen
authors.initials: H
authors.lastname: de Weerd
authors.forename: Edel
authors.initials: E
authors.lastname: Flannery
authors.forename: Julian R
authors.initials: JR
authors.lastname: Marchesi
authors.forename: Daniel
authors.initials: D
authors.lastname: Falush
authors.forename: Timothy
authors.initials: T
authors.lastname: Dinan
authors.forename: Gerald
authors.initials: G
authors.lastname: Fitzgerald
authors.forename: Catherine
authors.initials: C
authors.lastname: Stanton
authors.forename: Douwe
authors.initials: D
authors.lastname: van Sinderen
authors.forename: Michael
authors.initials: M
authors.lastname: O'Connor
authors.forename: Norma
authors.initials: N
authors.lastname: Harnedy
authors.forename: Kieran
authors.initials: K
authors.lastname: O'Connor
authors.forename: Colm
authors.initials: C
authors.lastname: Henry
authors.forename: Denis
authors.initials: D
authors.lastname: O'Mahony
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Fitzgerald
authors.forename: Fergus
authors.initials: F
authors.lastname: Shanahan
authors.forename: Cillian
authors.initials: C
authors.lastname: Twomey
authors.forename: Colin
authors.initials: C
authors.lastname: Hill
authors.forename: R Paul
authors.initials: RP
authors.lastname: Ross
authors.forename: Paul W
authors.initials: PW
authors.lastname: O'Toole
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001419:Bacteria / Q000145:classification* / Q000235:genetics; D001483:Base Sequence; D016000:Cluster Analysis; D019295:Computational Biology; D005243:Feces / Q000382:microbiology; D006801:Humans; D007422:Intestines / Q000382:microbiology*; D007494:Ireland; D054892:Metagenome / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D025341:Principal Component Analysis; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013045:Species Specificity; D018709:Statistics, Nonparametric
chemical_list: D012336:RNA, Ribosomal, 16S