Role of the Gut Microbiome in Complex Regional Pain Syndrome

November 3, 2025 updated by: Washington University School of Medicine
The objective of this prospective, observational study is to determine the association between the composition of the gut microbiota and the severity and persistence of Complex Regional Pain Syndrome symptoms (Study A). The objective of Study B, a longitudinal study of microbiota biomarkers of patients with newly diagnosed CRPS is to determine if the researchers can predict which patients are more likely to recover compared to those who do not. A secondary objective of both studies is to examine cognitive flexibility in relation to outcomes (study A and B).

Study Overview

Status

Recruiting

Conditions

Study Type

Observational

Enrollment (Estimated)

140

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • United States
    • Missouri
      • St Louis, Missouri, United States, 63110
        • Recruiting
        • Washington University School of Medicine
        • Principal Investigator:
          • Laura Crock, MD
        • Contact:
          • Laura Crock, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Sampling Method

Non-Probability Sample

Study Population

Pain Management Center at Washington University/Barnes-Jewish Hospital medical campus

Description

Study A: Cross-sectional study

Inclusion criteria, cases:

  • Adults over the age of 18
  • Current (< 1 year duration) or former (> 1 year) diagnosis of Complex Regional Pain Syndrome by the Budapest criteria
  • English as primary language
  • able to consent

Inclusion criteria, controls

  • Adults over age of 18
  • Cohabitant of person with current or former diagnosis of CRPS

Study B: Longitudinal Study

Inclusion criteria, cases:

  • Adults over the age of 18
  • Recent diagnosis (<6 months) of Complex Regional Pain Syndrome by the Budapest criteria
  • English as primary language
  • able to consent

Inclusion criteria, controls

  • Adults over age of 18
  • Cohabitant of person with diagnosis of CRPS

Study A and B: Exclusion criteria, cases and controls:

  • Unwilling to participate in the study
  • Lives alone
  • Current use of probiotics and unwilling to stop for 1 week prior to stool sample
  • Pregnant or lactating
  • Vegan diet

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Cohort
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Study A: Chronic >1 year
Study A: Acute <1 year
Study A: Household Control
Study B: Newly Diagnosed <6 months
Study B: Household Controls

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Number of participants with taxonomic and metabolomic differences of the gut microbiome in relation to CRPS severity score
Time Frame: 1 visit - up to one month
Study A
1 visit - up to one month
Number of participants with taxonomic and metabolomic differences of the gut microbiome in relation to recovery from CRPS
Time Frame: 12 months
Study B
12 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Score results of the Stroop Color Word Test in relation to CRPS recovery
Time Frame: 12 months
Study B
12 months
Logistic regression analysis for testing the association of CRPS severity score to weight in kilograms and height in meters aggregated to BMI (kilograms/meters squared)
Time Frame: 12 months
Study B
12 months
Logistic regression analysis for testing the association of CRPS severity score to use of opioid analgesics
Time Frame: 12 months
Study B
12 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Washington University School of Medicine

Investigators

  • Principal Investigator: Lara Crock, MD PhD, Washington University School of Medicine

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 19, 2018

Primary Completion (Estimated)

July 1, 2027

Study Completion (Estimated)

July 1, 2027

Study Registration Dates

First Submitted

July 9, 2018

First Submitted That Met QC Criteria

August 1, 2018

First Posted (Actual)

August 2, 2018

Study Record Updates

Last Update Posted (Estimated)

November 5, 2025

Last Update Submitted That Met QC Criteria

November 3, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 201806182

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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