Microbiome of the Ageing Gut and Its Effect on Human Gut Health and Cognition.

The investigators aim to undertake a 49-month longitudinal study in a cohort of 360 healthy individuals of 60 years and older, living in East Anglia to understand the role of gut microbes (the microbiome) in healthy ageing. The investigators also aim to identify changes in the structure and function of the gut microbe populations that are associated with deteriorating mental health and cognitive function. Using clinically validated cognitive assessments and tests, study participants will be stratified in to one of three risk groups for developing dementia:- Cohort 1 - low (n=120). Cohort 2 - medium (n=120). Cohort 3 - high (n=120). Participants will be recruited from three streams - Primary Care, The NHS Bowel Cancer Screening Programme (BCSP) and the Norfolk \& Suffolk Foundation Trust (NSFT). Following initial Telephone Contact and the Pre-Study Visit, all participants will be required to attend the Quadram Institute Clinical Research Facility (QI CRF) every 6 months over 4 years. At each of these follow-up visits, the participant will provide a stool sample (collected at home) and at differing time points, provide a blood sample and undergo a series of physical measurements, cognitive tests/questionnaires and complete a health questionnaire. All participants will undergo Optical Coherence Tomography scans at the Beccles \& District War Memorial Hospital. There will be 2 subgroups in this study. Subgroup 1 - at least 30 participants from each cohort (n= at least 90) will undergo colonic tissue biopsies as part of routine clinical care using the NHS BCSP. Subgroup 2 - 30 participants from Cohort 3 will undergo brain imaging at the Norfolk \& Norwich University Hospital (NNUH) Imaging Department. The results of the study will provide new insights into the gut-brain axis and the relationship between age-associated changes in gut microbe populations and declining mental health. Such insights will be of enormous value in developing new microbe-based strategies to improve lifelong health and wellbeing that impact on dementia development.

NCT Number	NCT04199195
Lead Sponsor	Quadram Institute Bioscience Collaborators: Norfolk and Norwich University Hospitals NHS Foundation Trust
Conditions	Ageing
Enrollment	360 participants
Start Date	2019-09-01
Primary Completion	2028-04-01 (estimated)
Study Completion	2028-04-01 (estimated)
Updated on ClinicalTrials.gov	2025-03-20