NCT07799402 · RECRUITING
Microbiome in Aging of Gut and Brain
This is an observational study, so nobody is given a drug or treatment. Researchers collect stool, saliva, blood and urine samples, plus memory and diet information. They want to see whether gut and mouth bacteria differ by cognitive health, and how they change over up to 5 years. No phase applies.
Eligibility criteria
Inclusion Criteria: * Age 18-60 years for young healthy participants, or age 60 years and older for older adult participants. * Participants meeting one of the following cognitive categories: * Normal cognitive function * Mild cognitive impairment (MCI) * Alzheimer's disease or Alzheimer's disease-related dementia * Able to participate in the informed consent process as applicable. * For participants unable to provide informed consent because of cognitive impairment, consent may be obtained from a legally authorized representative (LAR) according to the approved protocol. Exclusion Criteria: * History of brain or gastrointestinal surgery within the past 5 years. * History of cancer and/or cancer treatment within the past 5 years, except non-melanoma skin cancer. * History of systemic cancer treatment within the past 5 years. * Neurological disorders including epilepsy, Parkinson's disease, or amyotrophic lateral sclerosis. * Antibiotic use within the past 30 days. * Diarrhea, vomiting, and/or food poisoning within the past 30 days. * History of inflammatory bowel disease. * Body mass index (BMI) greater than 45 kg/m² or less than 18 kg/m². * Weight loss of more than 10 pounds within the past 2 weeks.
The sponsor's own eligibility wording, lightly reformatted. The study team makes the final eligibility decision — worth discussing with your doctor.
Eligibility criteria as of 2026-09-21