The Effect of Probiotic Supplementation on Cognitive and Emotional Functions in Healthy Elderly Subjects

Not Applicable

Completed

Interventions: Dietary Supplement: Placebo
Dietary Supplement: Lactobacillus rhamnosus and Bifidobacterium lactis

Brief Summary: This study evaluates the cognitive and emotional effects of probiotics in healthy elderly patients.

Detailed Description: Gut microbiota (GM) has focused as an important target for emotional and cognitive diseases, moreover in a population that show an altered GM such as elderly population as age-related changes. Several studies have shown that ageing alter GM, both in diversity and integrity.

Probiotics have demonstrated that correct or prevent age-related dysbiosis, in order to reduce or prevent intestinal permeability and associated inflammation, inhibit the generation of harmful and/or toxic metabolites, as well as promote the production of beneficial bacterial components.

The aim of this study is to assess the effectiveness of a multiprobiotic formulation as a therapeutic strategy to attenuate the emotional and cognitive decline associated with ageing in healthy adults over 55 years of age. The hypothesis is that administration of a multi-species probiotic for 10 weeks will slow and/or ameliorate the decline in emotional and cognitive function inherent to senescence.

Recruitment & Eligibility

Inclusion Criteria

be aged 55 years or over,
voluntarily agree to participate in the study in accordance with the Helsinki declaration,
not be participating in another study that could interfere with the results.

Exclusion Criteria

suffer from any serious mental illness other than depression and anxiety,
score below 10 on the Mini-Mental State Examination (MMSE) (severe cognitive impairment)
be using medications that affect cognition,
taking anti-inflammatory drugs, antipsychotics, antibiotics and/or anxiolytics,
have a serious illness (e.g. cancer, Parkinson's or Alzheimer's).

Arm && Interventions

Group	Intervention	Description
Placebo group	Placebo	Participants will receive a harmless substance (potato starch) during 10 weeks.
Probiotic group	Lactobacillus rhamnosus and Bifidobacterium lactis	Participants will be treated with a daily capsule of a multi-species probiotic (3.3 billion Lactobacillus rhamnosus and Bifidobacterium lactis) during 10 weeks.

Primary Outcome Measures

Name	Time	Method
Change from Baseline Depression at 10 weeks	Before and after treatment (10 weeks)	The Beck Depression Inventory. Score range: 0-63.
Change from Baseline General Cognitive Status at 10 weeks	Before and after treatment (10 weeks)	Mini-Mental State Examination. Score range: 0-35
Change from Baseline Motor impulsivity or inhibitory response at 10 weeks	Before and after treatment (10 weeks)	Go/No-Go task
Change from Baseline Planning Ability at 10 weeks	Before and after treatment (10 weeks)	Tower of London test
Change from Baseline Problem-solving ability at 10 weeks	Before and after treatment (10 weeks)	Wisconsin Card Sorting test
Change from Baseline Visual Attention at 10 weeks	Before and after treatment (10 weeks)	Trail Making Test
Change from Baseline Selective attention, cognitive flexibility and response inhibition at 10 weeks	Before and after treatment (10 weeks)	Stroop task
Change from Baseline Anxiety at 10 weeks	Before and after treatment (10 weeks)	The State-Trait Anxiety Inventory. Score range: 20-80
Change from Baseline Working Memory at 10 weeks	Before and after treatment (10 weeks)	Digits task, Corsi task
Change from Baseline Choice impulsivity or impulsive decision-making at 10 weeks	Before and after treatment (10 weeks)	Iowa Gambling Task

Secondary Outcome Measures

Name	Time	Method
Change from Baseline Body Composition at 10 weeks	Before and after treatment (10 weeks)	Fat mass. Body fat mass. Fat-free mass. Total body water.
Change from Baseline Gastrointestinal Symptom at 10 weeks	Before and after treatment (10 weeks)	Gastrointestinal Symptom Rating Scale
Change from Baseline Food Habits at 10 weeks	Before and after treatment (10 weeks)	"24-hour recall" questionnaire
Change from Baseline Sleep Quality at 10 weeks	Before and after treatment (10 weeks)	The Pittsburgh Sleep Quality Index Questionnaire. Score range: 0-21
Change from Baseline Stool Consistency at 10 weeks	Before and after treatment (10 weeks)	The Bristol Scale
Change from Baseline Perceived Stress at 10 weeks	Before and after treatment (10 weeks)	Perceived Stress Questionnaire. Score range: 0-1
Change from Baseline Alcohol Use at 10 weeks	Before and after treatment (10 weeks)	The Alcohol Use Disorders Identification Test. Score range: 0-40
Change from Baseline Physical Activity at 10 weeks	Before and after treatment (10 weeks)	International Physical Activity Questionnaire

Locations (2): Pablo Roman
🇪🇸
Almeria, Spain
Universidad de Almeria
🇪🇸
La Cañada de San Urbano, Almeria, Spain