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Updated: Aug 24, 2026

A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment
12:18

A Machine Learning Approach to Design an Efficient Selective Screening of Mild Cognitive Impairment

Published on: January 11, 2020

Characterization of the intestinal microbial profile in mild cognitive impairment and Alzheimer's disease

Martin Medrano1, Mar Pacheco-Herrero2, Zunilda Borges3

  • 1Pontificia Universidad Católica Madre y Maestra, Vicerrectoría de Investigación e Innovación y Escuela de Medicina, Santiago de los Caballeros, República Dominicana.

Dementia & Neuropsychologia
|August 22, 2026
PubMed

Insights

Gut microbiota alterations are linked to Alzheimer's disease (AD) and mild cognitive impairment (MCI) in the Dominican Republic. Specific bacterial changes were observed, influenced by diet, in this Hispanic population.

Area of Science:

  • Neuroscience
  • Microbiology
  • Genetics

Background:

  • Alzheimer's disease (AD) and mild cognitive impairment (MCI) are leading causes of dementia, with increasing prevalence in Latin America.
  • Gut microbiota dysbiosis is implicated in neurodegeneration, yet data from Hispanic populations remain scarce.

Purpose of the Study:

  • To characterize the gut microbiota in individuals with AD, MCI, and healthy controls in the Dominican Republic.
  • To investigate associations between gut microbiota composition and clinical, demographic, and dietary factors in a Hispanic cohort.

Main Methods:

  • A prospective-translational study involving 88 participants aged 60 years and older.
  • 16S rRNA gene sequencing of stool samples analyzed using QIIME2 and R for microbial diversity, taxonomy, and differential abundance.
  • Dietary influences on gut microbiota were assessed using PERMANOVA.

Main Results:

  • No significant differences in alpha or beta diversity were found between AD, MCI, and control groups.
  • Abundance of Desulfobacterota was higher in MCI and AD groups compared to controls (p<0.05).
  • Specific genera (Bilophila, Odoribacter, Parabacteroides) increased, while others (Mitsuokella, Eubacterium ruminantium) decreased in MCI/AD. The Firmicutes/Bacteroidota ratio was lower in men with MCI. Dietary factors like mango, lettuce, and carrot influenced specific taxa.

Conclusions:

  • This study provides the first characterization of gut microbiota in AD and MCI within the Dominican Republic, revealing microbial shifts associated with cognitive impairment.
  • Findings highlight the role of regional dietary and ethnic factors in shaping the gut microbiome in this population.
  • Further longitudinal and multi-omics studies are recommended to establish causality and explore therapeutic potential.
Keywords:
Alzheimer DiseaseCognitive DysfunctionDominican RepublicDysbiosisGastrointestinal Microbiome

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