Vanderbilt Clinical Trials

Stress and Opioid Misuse Risk: The Role of Endogenous Opioid and Endocannabinoid Mechanisms

Purpose

The purpose of this study is to see how stress influences the effects of opioid pain medications often used to help relieve back pain. The study will help to learn more about how high stress levels could increase risk for pain medication misuse.

Conditions

Opioid Use Disorder
Back Pain
Stress

Eligibility

Eligible Ages: Over 18 Years
Eligible Genders: All
Accepts Healthy Volunteers: No

Inclusion Criteria

Intact cognitive status and ability to provide informed consent - Ability to read and write in English sufficiently to understand and complete study questionnaires (which are only validated in English) - Age 18 or older And - Presence of persistent daily low back pain of at least three months duration and of at least a 3/10 in average intensity

Exclusion Criteria

History of renal or hepatic dysfunction - Reports of current or past alcohol or substance abuse or treatment for such condition - A reported history of PTSD, psychotic, or bipolar disorders - Chronic pain due to malignancy (e.g., cancer) or autoimmune disorders (e.g., rheumatoid arthritis, lupus) - Reports of recent benzodiazepine use (confirmed via rapid urine screening prior to each lab session) - Any medical conditions (e.g., significant cardiovascular disease) that the study physician feels would contraindicate participation in the lab stressors - Reported daily opiate use within the past 6 months, or use of any opioid analgesic medications within 3 days of study participation (confirmed through rapid urine screening prior to each lab session) - Pregnancy (females only, to avoid fetal drug exposure - pregnancy tests conducted prior to each lab session to confirm eligibility) - Prior allergic reaction/intolerance to oxycodone or its analogs

Study Design

Phase: N/A
Study Type: Interventional
Allocation: N/A
Intervention Model: Single Group Assignment
Intervention Model Description: The study will be a mixed between/within-subjects design with double-blind counterbalanced placebo-controlled administration of both an opioid antagonist and an opioid agonist. Both drugs are being administered solely to probe mechanisms linking stress with individual differences in opioid analgesic responses (this is not an efficacy trial).
Primary Purpose: Basic Science
Masking: None (Open Label)
Masking Description: The participant and investigator will be blinded to the drug order across the 3 laboratory drug administration sessions.

Arm Groups

Arm	Description	Assigned Intervention
Other Adults with chronic non-cancer low back pain		Drug: Placebo In randomized order (crossover) across 3 laboratory sessions, participants will undergo laboratory evoked thermal pain response testing with: 1) 0.13 mg/kg of oral oxycodone (in 1mg/ml syrup) plus 20ml i.v. saline placebo, 2) 8mg of i.v. naloxone (in 20ml saline vehicle) plus oral placebo syrup (quantity matching oxycodone syrup volume), or 3) 20ml i.v. saline placebo plus oral placebo syrup (quantity matching oxycodone syrup volume). Thermal pain testing utilizes a Medoc TSAII NeuroSensory Analyzer. This equipment is used to assess heat pain threshold and tolerance using an ascending method of limits protocol. Other names: normal saline placebo Drug: Oxycodone In randomized order (crossover) across 3 laboratory sessions, participants will undergo laboratory evoked thermal pain response testing with: 1) 0.13 mg/kg of oral oxycodone (in 1mg/ml syrup) plus 20ml i.v. saline placebo, 2) 8mg of i.v. naloxone (in 20ml saline vehicle) plus oral placebo syrup (quantity matching oxycodone syrup volume), or 3) 20ml i.v. saline placebo plus oral placebo syrup (quantity matching oxycodone syrup volume). Thermal pain testing utilizes a Medoc TSAII NeuroSensory Analyzer. This equipment is used to assess heat pain threshold and tolerance using an ascending method of limits protocol. Drug: Naloxone In randomized order (crossover) across 3 laboratory sessions, participants will undergo laboratory evoked thermal pain response testing with: 1) 0.13 mg/kg of oral oxycodone (in 1mg/ml syrup) plus 20ml i.v. saline placebo, 2) 8mg of i.v. naloxone (in 20ml saline vehicle) plus oral placebo syrup (quantity matching oxycodone syrup volume), or 3) 20ml i.v. saline placebo plus oral placebo syrup (quantity matching oxycodone syrup volume). Thermal pain testing utilizes a Medoc TSAII NeuroSensory Analyzer. This equipment is used to assess heat pain threshold and tolerance using an ascending method of limits protocol. Other names: narcan

Recruiting Locations

Vanderbilt University Medical Center
Nashville, Tennessee 37212

Contact:
Stephen Bruehl, PhD

More Details

Status: Recruiting
Sponsor: Vanderbilt University Medical Center

Study Contact

Stephen Bruehl, PhD
615-936-1821
stephen.bruehl@vumc.org

Detailed Description

The purpose of this project is to advance mechanistic knowledge of how stress impacts differential opioid analgesic responses that enhance risk for opioid use disorder (OUD), potentially informing development of data-driven precision pain medicine algorithms to mitigate opioid related risks. The study aims to determine whether subjective and physiological stress-related measures are associated with analgesic and misuse-relevant subjective responses to placebo-controlled oxycodone administration. The study also aims to evaluate associations between stress-related measures and both endogenous opioid (EO) function and endocannabinoid (EC) levels and to test whether EO and EC mechanisms contribute to associations between stress-related measures and oxycodone responses Using a mixed between/within-subject design, the study will obtain baseline assessment of stress related markers followed by 3 laboratory sessions with assessment of endocannabinoids, back pain assessment, and exposure to standardized evoked pain stimuli after administration of placebo, naloxone, and oxycodone.