Effect of human probiotics on memory, psychological and biological measures in elderly: A study protocol of bi-center, double-blind, randomized, placebo-controlled clinical trial (CleverAge Biota)

Abstract

BackgroundGut microbiota may influence brain functions. Therefore, we prepared a study protocol for a double-blind, crossover, randomized clinical trial to determine the complex effects of human probiotics on memory, psychological, and biological measures in the elderly.MethodsWe selected eligible participants using an effective electronic questionnaire containing the inclusion and exclusion criteria and a brief electronic cognitive test. One-third of the respondents with the worst cognitive scores on the electronic test are randomized to group A, starting with a 3-month probiotic intervention, and to group B, starting with a placebo. In a crossover design, both groups change their intervention/placebo status after 3 months for the next 3 months. Participants refusing longer personal assessments due to the COVID-19 pandemic were randomly allocated to one of two subgroups assessed online. Participants in both groups are matched in age, education, gender, and cognitive scores on electronic testing at baseline. At three time points, participants are assessed using a neuropsychological battery, self-report measures of mood, a physical fitness test, blood, urine, and stool samples, and actigraphy. A subset of participants also provided their biological samples and underwent the neuropsychological battery in an extended testing phase 3 months after study termination to find out the long-term effect of the intervention.DiscussionThis is the first trial to address the comprehensive effects of human probiotics on memory and many other measures in the elderly. We assume that the probiotic group will have better outcomes than the placebo group after the first and second trimesters. We expect that the probiotic effect will persist for the next 3 months. These study’s findings will contribute to an interesting area of how to improve memory, psychological and biological and other factors naturally and will examine the importance of probiotics for overall health in the elderly.Clinical trial registration[clinicaltrials.gov], identifier [NCT05051501].

Effects of human probiotics on memory and psychological and physical measures in community-dwelling older adults with normal and mildly impaired cognition: results of a bi-center, double-blind, randomized, and placebo-controlled clinical trial (CleverAge biota)

“…The detailed protocol for this study can be found in our previous paper ( Bartos et al, 2022 ). Here we briefly describe participants´ characteristics and procedures.…”

“…Due to the controversies within this evolving area of study, we decided to design a randomized clinical trial with a cross-over design ( Bartos et al, 2022 ). Studies focusing on cognitively normal or mildly affected older adults are scarce ( Tahmasbi et al, 2022 ).…”

Update on modifiable risk factors for Alzheimer's disease and related dementias

“…Several randomized, double-blind, placebo-controlled clinical trials have evaluated the efficacy of probiotics in patients with MCI with mixed results [5,10,122]. In addition, the safety and feasibility of oral fecal microbiota transplant is being evaluated [23].…”

Alterations in microbiota of patients with COVID‐19: implications for therapeutic interventions

“…In this situation, whether probiotic adjuvant therapy may improve the regulation of neuroinflammation is a crucial consideration for future investigations. The potential cognitive benefits of probiotic adjuvant therapy are worth looking forward to 174 . A recent clinical cross‐sectional study demonstrated a correlation between alterations in the gut microbiome composition of patients with AD and β‐amyloid and tau pathological biomarkers, suggesting that changes in the gut microbiome may occur early in the disease process and have an association with cognitive impairment.…”

“…The potential cognitive benefits of probiotic adjuvant therapy are worth looking forward to. 174 A recent clinical cross‐sectional study demonstrated a correlation between alterations in the gut microbiome composition of patients with AD and β‐amyloid and tau pathological biomarkers, suggesting that changes in the gut microbiome may occur early in the disease process and have an association with cognitive impairment. Probiotics may mitigate COVID‐19‐induced cognitive impairments through the regulation of neuroinflammation, modulation of the gut microbiota, and gut homeostasis.…”