The selection of participants for interventional microbiota trials involving cognitively impaired older adults

Gut microbiota plays a significant role in nutrient extraction, metabolism, and immune function. Thus, the growing number of microbiome studies seek to link the presence and prevalence of specific bacteria, fungi, and viruses with a variety of physiological and disease outcomes. However, recruiting a diverse group of patients has been a challenge. Poor hearing and vision, lack of transportation, cognitive impairment, and a non-English primary language may interfere with patient enrollment as well as adherence to the requirements of a Microbiome study. Much of what we do know about diseases in older adults comes from studies that exclude many of these patients commonly encountered in clinical practice. The purpose of this review article is to highlight recruitment and retention strategies for engaging people who typically do not participate in microbiome studies, and it seeks to develop and explicate inclusion and exclusion criteria to promote more robust study results.