Gut-brain Health Effects of PREbiotics in Older Adults With Suspected COgnitive DEcline

NCT06433037 | Active Not Recruiting

• 1 other identifier: NL85910.091.23
• Study Type: interventional
• Target: 164
• Locations: 1 country
• Sites: 1

Brief Summary

As people around the world are living longer, the number of individuals with dementia, particularly Alzheimer's disease (AD), is expected to triple by 2050. There's growing evidence suggesting that our gut health might play a role in the prevention of dementia. The connection between our gut and brain, known as the gut-brain axis, is becoming an important area of study. Research in animals has shown that different types of dietary fibre can improve gut health, brain function, mood, blood sugar level and the immune system and may even prevent certain harmful brain changes seen in Alzheimer's disease. Subjective Cognitive Decline (SCD) is a condition where individuals notice a decline in their mental abilities, and it can be an early sign of Alzheimer's disease. The goal of this clinical trial is to learn if dietary fibres can improve gut and brain health in older individuals, between the ages of 60 and 79 years, who notice problems in their mental abilities, and meet the criteria of SCD. Three different dietary fibres will be given, and researchers will compare three different fibres to a placebo product to see if there is a difference between the fibres and the placebo. The main questions it aims to answer are:

• Consume dietary fibres twice a day, mixed in water, tea or coffee, for a period of 26 weeks
• Have two functional MRI scans, and three additional study visits, where blood, urine and feces will be collected
• Undergo a number of neuropsychological tests, aimed at evaluating brain function
• Fill out questionnaires on their general health, mood, dietary habits, gut health
• Wear smartwatches for one week, at the beginning and the end of the study

Conditions

Subjective Cognitive Decline

Keywords

gut-brain axis; working memory; gut health; dietary fibres; prebiotics

Outcome Measures

Primary Outcomes (2)

• Effect on working memory during n-back task fMRI

  Effects on working memory will be assessed by blood-oxygen level dependant (BOLD) signal activity during 2-back task performed during fMRI scanning

  Measured at baseline and week 26

• Effect on working memory performance during n-back task fMRI

  Effects on working memory performance will be assessed by task accuracy during 2-back task performed during fMRI scanning

  Measured at baseline and week 26

Secondary Outcomes (25)

• Effect on cognitive functioning as measured by a neuropsychological test battery

  Measured at baseline, week 13 and week 26

• Effect on ADAS-Cog Word Recall cognitive assessment (episodic memory)

  Measured at baseline, week 13 and week 26

• Effect on ADAS-Cog Word Recognition cognitive assessment (episodic memory)

  Measured at baseline, week 13 and week 26

• Effect on Digit Symbol Substitution Test cognitive assessment (executive function)

  Measured at baseline, week 13 and week 26

• Effect on Digit Span Backward Task cognitive assessment (working memory)

  Measured at baseline, week 13 and week 26

Other Outcomes (7)

• Effect on heart rate

  Measured at baseline and week 26

• Effect on physical activity

  Measured at baseline and week 26

• Effect on BMI

  Measured at baseline, week 13 and week 26

Study Arms (4)

Maltodextrin

PLACEBO COMPARATOR

Dietary Supplement: Placebo

Chicory inulin

EXPERIMENTAL

Dietary Supplement: Chicory inulin

Resistant dextrin

EXPERIMENTAL

Dietary Supplement: Resistant dextrin

Seaweed polysaccharide

EXPERIMENTAL

Dietary Supplement: Seaweed polysaccharide

Interventions

Chicory inulin DIETARY_SUPPLEMENT

Chicory inulin (12g/day) divided over two dosages (6g per dose)

Chicory inulin

Resistant dextrin DIETARY_SUPPLEMENT

Resistant dextrin (14g/day) divided over two dosages (7g per dose)

Resistant dextrin

Seaweed polysaccharide DIETARY_SUPPLEMENT

Seaweed polysaccharide (1g/day) divided over two dosages (0.5g per dose). Additionally contains 7g/day of placebo as a volumetric and isocaloric filler.

Seaweed polysaccharide

Placebo DIETARY_SUPPLEMENT

Maltodextrin (7g/day) will be provided in two divided doses (3.5g per dose)

Maltodextrin

Eligibility Criteria

• Age: 60 Years - 79 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Written informed consent
• Fluency in Dutch (speaking, reading, writing)
• Age between 60-79 years (at screening)
• Subjective cognitive decline plus (SCD+), (criteria of Jessen et al.):
• Self-reported worsening of memory; 4.2 Indication of repetitive concerns (worries) associated with SCD; 4.3 With at least one of the following two features present: (i) onset of SCD within the last 5 years; (ii) age at onset ≥60 years of age;
• \. Presence of at least 2 self-reported risk factors for cognitive decline (based on LIBRA criteria): (i) Diabetes mellitus type II (ii) High cholesterol (iii) Hypertension (iv) High BMI (v) Heart disease (vi) Unhealthy diet (lower regular adherence to Mediterranean diet components such as fish, vegetables, olive oil, pasta and red wine)

You may not qualify if:

• Current participation in other intervention trials
• Technologically illiterate (complete incompetence in working with computers, apps, online questionnaires, smartwatches etc.)
• No internet access from home
• Clinical diagnosis of ≥1 of the following:
• Neurological pathology (e.g. MCI, dementia, multiple sclerosis, Parkinson's disease, epilepsy);
• Current malignant disease(s), with or without treatment;
• Current psychiatric disorder(s) (e.g. major depressive disorder, bipolar disorder, schizophrenia, anxiety, psychosis, PTSD);
• Symptomatic/decompensated cardiovascular disease (e.g. stroke, angina pectoris, heart failure, recent myocardial infarction);
• Severe visual impairment or blindness
• Hearing or communicative impairment.
• Gastrointestinal tract disorder such as irritable bowel syndrome or inflammatory bowel disease (e.g. Crohn's disease or ulcerative colitis).
• Current or recent (\<6 weeks) use of prebiotic, probiotic, or dietary fibre supplement that may modulate the microbiota, or unwilling to stop the use of supplements during the study
• Current or recent (\<6 weeks) of algae/phytoplankton supplements such as spirulina or chlorella, or unwilling to stop the use of supplements during the study
• Use of psychotropic medication (anti-depressants, anti-psychotics)
• Use of antibiotics in the 3 months before starting the study or planned use during the study

Sponsors & Collaborators

• Wageningen University: lead
• Sensus BV: collaborator
• Cosun Nutrition Center: collaborator
• Roquette Frères: collaborator
• Oceanium Ltd.: collaborator
• Technical University of Eindhoven (TU/e): collaborator

Study Sites (1)

Wageningen University

Wageningen, Netherlands

Location

Related Links

• PRECODE study Wageningen University

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor in Nutrition, Brain and Cognitive Aging

Model Details: Randomised, double-blinded, placebo-controlled intervention study with parallel design and four arms.

Study Record Dates

• First Submitted: May 17, 2024
• First Posted: May 29, 2024
• Study Start: July 16, 2024
• Primary Completion: January 1, 2026
• Study Completion (Estimated): April 1, 2027
• Last Updated: August 26, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

NL (1)