Clinical Trial Details
— Status: Recruiting
Administrative data
NCT number |
NCT05304403 |
Other study ID # |
801745 |
Secondary ID |
|
Status |
Recruiting |
Phase |
|
First received |
|
Last updated |
|
Start date |
April 1, 2022 |
Est. completion date |
June 1, 2025 |
Study information
Verified date |
July 2023 |
Source |
University of California, San Diego |
Contact |
Rodney A Gabriel, MD |
Phone |
8582493660 |
Email |
ragabriel[@]health.ucsd.edu |
Is FDA regulated |
No |
Health authority |
|
Study type |
Observational
|
Clinical Trial Summary
The United States is in the midst of an opioid epidemic, with the number of opioid-related
deaths having risen six-fold since 1999. Chronic pain imposes a tremendous economic burden of
up to US$635 billion per year in terms of direct costs (such as the costs of treatment) and
indirect costs (such as lost productivity and time away from work). We need to better
understand individual characteristics that may put patients at risk for chronic opioid use.
Recently, the relationship between gut microbiome and diseases of the central and peripheral
nervous systems has received increasing attention. New evidence suggests that gut microbiota
may also play a critical role in many types of chronic pain, including inflammatory pain,
neuropathic pain, and opioid tolerance. Many signaling molecules derived from gut microbiota,
such as pathogen-associated molecular patterns, metabolites, and neurotransmitters, act on
receptors that regulate the peripheral and central sensitization, which in turn mediate the
development of chronic pain. Gut microbiota-derived mediators serve as critical modulators
for the induction of peripheral sensitization, directly or indirectly regulating the
excitability of primary nociceptive neurons. Given the strong evidence supporting gut
microbiome's involvement in pain pathways, there is a need to develop studies that
characterize the differences in gut microbiome between chronic pain patients requiring
opioids versus healthy controls. The objective of this proposal is to perform a pilot study
measuring the predictive ability of the gut microbiome with chronic opioid use - this will
then lay the groundwork to adequately power a larger funded prospective study.
Description:
The investigators hypothesize that there will be distinct characteristics in the composition
of the microbiome in chronic opioid users versus healthy controls (controls identified from
national database). Consenting patients (n~ 100) - who will be identified in the
institution's chronic pain clinic - will provide fecal samples for microbiome composition
analysis. In addition, additional data will be collected including patient age, sex, body
mass index, comorbidities, opioid dosing/frequency, pain scores, and pain characteristics.
This additional information will be ascertained by a basic intake form and the Brief Pain
Inventory. The investigators have access to the Human Microbiome Project Database and will
obtain matched samples to represent healthy controls (retrospective publicly available
database).
Consent: After pre-screening eligible patients from the chronic pain clinic, patients will
either be consented in person (at their clinic visit), which in that case they will fill out
the intake surveys in-person and be provided to take home a microbiome kit. The kit will
require patients to swab their stool. This will then be mailed back to the invsestigators.
All shipping will be pre-paid by the research team. Patients may also be consented via the
phone, in which case, the consent form will be signed via HIPAA-secure DocuSign. Surveys will
then be sent to patient via email through Redcap services. The microbiome kit will be mailed
to the patient's residence.
Statistical Analysis: The microbiome data is highly dimensional and will therefore be
analyzed using several approaches. Compositional data will be assessed using the QIIME2
pipeline where alpha and beta diversity measures, and taxonomic relative abundances will be
compared using standard non-parametric and linear models (Wilcoxon Rank-Sum and
Kruskal-Wallis tests are most common based on standard microbiome data). Secondary analyses
will include comparing microbiome compositions among subsets of chronic opioid users based on
their overall daily dosing.
Sample Size Calculation: As this is a pilot study, the investigators did not perform a power
analysis. Rather, they will recruit 100 subjects. The results from this study will be used to
help design and power a larger funded prospective study.