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Probiotics in Dementia

Not Applicable
Completed
Conditions
Dementia; Alzheimer, Mixed Type (Etiology)
Interventions
Dietary Supplement: placebo
Dietary Supplement: Omni-Biotic Stress Repair
Registration Number
NCT03847714
Lead Sponsor
Medical University of Graz
Brief Summary

Dementia is associated with changes in gut microbiome composition, gut barrier dysfunction, intestinal inflammation and systemic inflammation. Probiotics are a possibility to modulate the gut-brain axis. In this study the effect of probiotics on the gut microbiome and, gut barrier function, inflammation and cognitive dysfunction will be studied.

Detailed Description

Dementia is a disease that presents with deterioration in memory, thinking, behaviour and the ability to perform everyday activities. Worldwide 47.5 million people are affected and incidence of dementia is increasing. Dementia leads to disability and dependency among older people worldwide and thereby has a huge physical, psychological, social and economic impact on caregivers, families and society. Alzheimer's disease (AD) is the most common form of dementia accounting for 60-70% of the cases; other forms include Lewy body dementia, frontotemporal dementia, vascular dementia and Parkinson's disease with dementia. In AD, pathologic protein aggregates of amyloid beta and hyperphosphorylated tangles of tau-protein which deposit as neurofibrillary tangles are typical features. This leads to neuroinflammation, mainly mediated by the innate immune system. The most important cells in this process are microglia cells, which represent the resident macrophages of the brain. Although microglia is able to remove extracellular amyloid beta, in later stages of the disease cells remain in a dystrophic state and cannot exert their beneficial functions. Microglia maturation and function is critically dependent on short-chain fatty acids produced by the gut microbiome and therefore highlights the microbiome as a potential diagnostic and therapeutic target in dementia.

The role of the commensal microbial population of the human body - especially the intestinal microbiome - in various diseases is emerging due to the development of advanced analysis techniques. Recently the concept of the gut brain-axis has been established. Several pathways including the autonomic nervous system, the enteric nervous system, the neuroendocrine system and the immune system allow a communication between gut and brain but may also be involved in disease development.

During ageing, the gut microbiome composition undergoes changes. A decrease in diversity, a loss of beneficial taxa and an increase of facultative pathogens has been described. Diet and the place of residence play an important role in the shaping of the microbiome. Aging is also associated with inflammation - often termed as "inflammaging" associated with an increase in gut permeability, mucosal inflammation and bacterial translocation.

Since the main risk factor for developing dementia, especially AD, is aging, it is very likely that the gut-brain axis is critically involved in dementia development.

Animal studies so far suggest that AD is associated with changes in the gut microbiome composition with a decrease in beneficial, anti-inflammatory genera. Furthermore, genetic alterations in amyloid genes can influence microbiome composition in mice, pointing towards a vicious cycle in AD development.

In humans, so far only limited evidence on the microbiome composition in patients with dementia is available. There is evidence that the composition of the microbiome in subgingival plaques is altered in dementia and associated with cognitive function. Recently the first human study identified phylum- through genus-wide differences in bacterial abundance including decreased Firmicutes, increased Bacteroidetes, and decreased Bifidobacterium in the stool of AD patients.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
17
Inclusion Criteria
  • Age >18 years
  • Dementia of Alzheimer type and mixed type (diagnosis by a board-certified neurologist/psychiatrist and according to ICD10)
  • Mini Mental State Examination 21-26
  • Stable treatment with anti-dementia drugs including phytotherapeutics (>3 months) or no intention to start anti-dementia drugs
  • Informed consent
Exclusion Criteria
  • Other forms of dementia
  • Inflammatory bowel diseases
  • Liver cirrhosis
  • Antibiotic treatment within the last 4 weeks
  • Febrile illness within the last 4 weeks
  • Acute hospital admission for dementia-unrelated reasons within the last 4 weeks
  • Dysphagia
  • Any other condition or circumstance, which, in the opinion of the investigator, would affect the patient's ability to participate in the protocol

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Placeboplacebo3g of a similar looking and tasting powder, twice daily
ProbioticOmni-Biotic Stress RepairBifidobacterium bifidum W23, B. lactis W51, B. lactis W52, Lactobacillus acidophilus W22, L. casei W56, L. paracasei W20, L. plantarum W62, L. salivarius W24, Lactococcus lactis W19, 7.5 × 109 Colony Forming Units/g twice daily dissolved in water
Primary Outcome Measures
NameTimeMethod
Butyrate producing bacteria6 months

abundance of butyrate producing bacteria

Secondary Outcome Measures
NameTimeMethod
Butyrate producing bacteria12 months

abundance of butyrate producing bacteria

soluble CD 14 concentration in serum12 months

marker of systemic inflammation

lipopolysaccharide concentration in serum12 months

marker of bacterial translocation

diaminooxidase concentration in serum12 months

marker of intestinal permeability

zonulin concentration in stool12 months

marker of intestinal permeability

Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS cog)12 months

Questionnaire to assess cognitive function, 0-70 points

calprotectin concentration in stool12 months

marker of intestinal inflammation

clinician's interview-based impression of change with caregiver input (CIBIC+)12 months

Questionnaire to assess overall change during the study, 1-7 points

lipopolysaccharide binding protein concentration in serum12 months

marker of systemic inflammation

Barthel index12 months

Assessment of activities of daily living, 0-100 points

peptidoglycan concentration in serum12 months

marker of bacterial translocation

bacterial DNA concentration in serum12 months

marker of bacterial translocation

Mini mental state examination12 months

Questionnaire to assess cognitive function, 0-30 points

Trial Locations

Locations (1)

Medical University Graz

🇦🇹

Graz, Austria

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