Oral Microbiome in Carotid Atherosclerosis

NCT07296965 | Recruiting

• 2 other identifiers: NKFI-Advanced 149634BM/33955-1/2023
• Study Type: observational
• Target: 200
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this observational study, called OMICA (Oral Microbiome in Carotid Atherosclerosis), is to learn how bacteria living in the mouth may influence the development and stability of plaques in the carotid arteries, which supply blood to the brain. Plaque buildup in these arteries can lead to stroke. Researchers want to understand whether certain oral bacteria are linked to plaque vulnerability, meaning a higher chance that the plaque will rupture and cause a stroke. The study will include a cohort of adults scheduled for carotid endarterectomy at Semmelweis University. Participants will be enrolled in the Semmelweis University Carotid Biobank project. The main questions the study aims to answer are: Do people with more severe gum disease or tooth infection have a higher number of bacteria in their carotid plaques, and are those plaques more likely to rupture? Are the bacteria found in vulnerable plaques different from those in stable plaques? Are similar bacteria found in the mouth, gut, and plaques, suggesting that bacteria may travel through the body? What participants will do: Have their oral health checked before surgery, including an exam of gum disease and tooth infections. Provide microbiome samples from the mouth, anus, urine, and carotid plaque (taken during surgery). Have preoperative photon-counting computed tomography (CT) performed to assess plaque stability and study eligibility. All samples and imaging data will be analyzed to identify bacterial species and their relationship to plaque type. The study does not involve any experimental treatment or medication. Participation adds no significant medical risk beyond standard care. Researchers will compare bacterial patterns between people with vulnerable plaques and those with stable plaques to identify microbial signatures linked to carotid plaque instability. The results may help create future microbiome-based risk models for detecting people at higher risk of stroke or severe atherosclerosis.

Conditions

Atherosclerosis Cardiovascular Disease; Atherosclerosis of Artery; Carotid Artery Plaque; Periodontitis; Carotid Artery Diseases

Keywords

Oral Microbiome; Carotid Plaque; Plaque vulnerability; Atherosclerosis; Periodontal disease; Biobank study; Microbial colonization

Outcome Measures

Primary Outcomes (1)

• Identification of Oral and Carotid Plaque Microbiome Associations

  Microbiome composition of oral and carotid plaque samples will be analyzed using next-generation sequencing to identify bacterial taxa correlated with plaque vulnerability. Relative abundance and diversity indices will be compared between participants with vulnerable and stable carotid plaques to determine microbial associations linked to plaque instability.

  At time of carotid endarterectomy

Secondary Outcomes (2)

• Differences in Microbiome Composition Between Vulnerable and Stable Carotid Plaques

  At time of carotid endarterectomy

• Identification of Shared Microbial Taxa Across Oral, Anal, Urine, and Carotid Plaque Samples

  At time of carotid endarterectomy

Other Outcomes (1)

• Correlation Between Oral Health Status and Carotid Plaque Vulnerability

  Within 2 weeks prior to carotid endarterectomy

Study Arms (2)

Vulnerable Plaque Group

Participants with vulnerable carotid plaques, identified based on ultrasound gray-scale median (GSM) score, photon-counting CT angiography, and MR plaque characterization.

Other: Sample Collection

Stable Plaque Group

Participants with stable carotid plaques, classified by imaging criteria indicating low vulnerability.

Other: Sample Collection

Interventions

Sample Collection OTHER

Participants undergo preoperative oral health evaluation and the collection of oral, anal, urine, blood, and carotid plaque samples during carotid endarterectomy for microbiome analysis. All samples are fully anonymized and processed within the Semmelweis University Carotid Plaque Biobank (BM/33955-1/2023). No experimental treatments are administered; all activities occur within the framework of biobank-approved surgical and diagnostic procedures.

Also known as: Oral-Systemic Microbiome Analysis, Carotid Plaque Microbiome Sampling

Stable Plaque Group; Vulnerable Plaque Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Participants will be recruited from patients undergoing carotid endarterectomy at Semmelweis University, Budapest, Hungary, within the framework of the Semmelweis Carotid Plaque Biobank. Eligible individuals are adults with confirmed internal carotid artery stenosis identified by photon-counting CT angiography. Enrollment is consecutive among surgical candidates who provide informed consent. The study population reflects a tertiary vascular surgery center cohort representing both stable and vulnerable plaque phenotypes, as classified by ultrasound, MR, and CTA imaging.

You may qualify if:

• Confirmed internal carotid artery (ICA) stenosis on preoperative photon-counting computed tomography (CTA)
• Adults (≥18 years) undergoing carotid endarterectomy at Semmelweis University.
• Eligible for surgery based on standard anesthesiologic evaluation.
• Willing and able to provide written informed consent for participation and sample collection.

You may not qualify if:

• Active systemic infection or current antibiotic therapy within 30 days before surgery.
• Immunosuppressive therapy or immunodeficiency disorders.
• Inability to undergo MRI (e.g., pacemaker, metallic implants, severe claustrophobia).
• Pregnancy or lactation.
• Malignancy under active treatment.
• Prior carotid surgery or stenting on the same side.
• Refusal or inability to provide informed consent.

Sponsors & Collaborators

• Semmelweis University Heart and Vascular Center: lead
• National Research, Development and Innovation Office, Hungary: collaborator

Study Sites (1)

Városmajor Heart and Vascular Center, Semmelweis University

Budapest, Hungary

RECRUITING

Related Publications (3)

• Isoshima D, Yamashiro K, Matsunaga K, Taniguchi M, Matsubara T, Tomida S, Ota S, Sato M, Shimoe Y, Kohriyama T, Arias Z, Omori K, Yamamoto T, Takashiba S. Microbiome composition comparison in oral and atherosclerotic plaque from patients with and without periodontitis. Odontology. 2021 Jan;109(1):239-249. doi: 10.1007/s10266-020-00524-w. Epub 2020 May 19.

  PMID: 32430725 BACKGROUND

• Brun A, Nuzzo A, Prouvost B, Diallo D, Hamdan S, Meseguer E, Guidoux C, Lavallee P, Amarenco P, Leseche G, Bouchard P, Michel JB, Range H. Oral microbiota and atherothrombotic carotid plaque vulnerability in periodontitis patients. A cross-sectional study. J Periodontal Res. 2021 Apr;56(2):339-350. doi: 10.1111/jre.12826. Epub 2020 Dec 25.

  PMID: 33368263 BACKGROUND

• Frencken JE, Sharma P, Stenhouse L, Green D, Laverty D, Dietrich T. Global epidemiology of dental caries and severe periodontitis - a comprehensive review. J Clin Periodontol. 2017 Mar;44 Suppl 18:S94-S105. doi: 10.1111/jcpe.12677.

  PMID: 28266116 BACKGROUND

Related Links

• Biobank
• Városmajor Biobank - Transplant Biobank

Biospecimen

Retention: SAMPLES WITH DNA

Oral swabs, anal swabs, urine samples, blood samples, and carotid plaque tissue obtained during carotid endarterectomy will be retained. Samples will be stored in the Semmelweis University Carotid Plaque Biobank (BM/33955-1/2023). DNA will be extracted for microbiome analysis using next-generation sequencing and may also be used for confirmatory molecular assays. All biospecimens will be de-identified and stored under controlled conditions for future research on vascular and microbial interactions.

MeSH Terms

Conditions

Carotid Stenosis; Periodontitis; Carotid Artery Diseases; Atherosclerosis; Periodontal Diseases; Communicable Diseases

Interventions

Specimen Handling

Condition Hierarchy (Ancestors)

Cerebrovascular Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Arterial Occlusive Diseases; Vascular Diseases; Cardiovascular Diseases; Mouth Diseases; Stomatognathic Diseases; Arteriosclerosis; Infections; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Investigative Techniques

Study Officials

• Péter Sótonyi, MD, DSc

  Semmelweis University Heart and Vascular Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Zsuzsanna Németh, MD, PhD

CONTACT

+36-30-261-1559; zsuzsannamihaly@gmail.com

Mathew J Mitchell, MD Candidate

CONTACT

+36-30-279-1038; mathew.mitchell@fulbrightmail.org

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 1 Year
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD, DSc, Head of Department of Vascular and Endovascular Surgery

Study Record Dates

• First Submitted: November 24, 2025
• First Posted: December 22, 2025
• Study Start: November 1, 2025
• Primary Completion (Estimated): November 1, 2027
• Study Completion (Estimated): November 1, 2029
• Last Updated: April 22, 2026

Record last verified: 2025-12

Locations

HU (1)