The Role of Opioidergic Systems in Breathing Based Analgesia

University of California San Diego

Status and phase: Completed; Early Phase 1

Conditions: Pain

Treatments: Other: Saline; Behavioral: Mindfulness Meditation; Behavioral: Placebo Meditation; Drug: Naloxone; Behavioral: Slow-Breathing

Study type: Interventional

Funder types: Other

Identifiers

NCT03419858

IRB00040519

Details and patient eligibility

About

The purpose of this psychophysical and pharmacologic study is to determine if slow-breathing induced pain relief is mediated by endogenous opioids in response to intravenous (IV) administration of the opioid antagonist naloxone during noxious heat stimulation. We were also interested in disentangling the endogenous analgesic mechanisms supporting mindfulness-based analgesia.

Full description

The proposed study will employ a graded analytical approach to compare mindfulness to placebo-meditation and a slow-breathing exercise in response to double-blind intravenous administration (IV) of naloxone/placebo-saline and noxious heat stimulation. The aim of this study is to determine if slow-breathing induced analgesia is associated with the release of endogenous opioids. The proposed study will disentangle the specific stage of cognitive and/or respiration-based involvement (if any) of opioidergically mediated pain relief, a critical step in identifying the specific analgesic mechanisms corresponding to mindfulness based cognitive techniques.

Enrollment: 60 patients

Sex: All

Ages: 18 to 55 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Normal volunteers with no history of chronic pain problems
• Volunteers had no prior meditation experience
• Volunteers could be male and non-pregnant females.
• Volunteers of all ethnic backgrounds were included.

Exclusion criteria

• Female volunteers could not be pregnant.
• They could not be taking opioids or antidepressants.
• Subjects with a repeated history of syncope, loss of consciousness, light headedness, nausea, dizziness, or vomiting in response to needles or blood could not participate in the study.
• Subject could not be using exogenous opiates for the complete duration of the study.

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Triple Blind

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60 participants in 3 patient groups

Mindfulness Meditation Group

Experimental group

Description:

Subjects participated in four sessions (20 min/session) of mindfulness training. Participants were taught that perceived sensory events are "momentary" and "fleeting" and require no further evaluation. They were asked to close their eyes, relax and to focus on the flow of their breathing and "simply let go" of discursive thoughts.

Treatment:

Other: Saline

Behavioral: Mindfulness Meditation

Drug: Naloxone

Placebo Meditation Group

Active Comparator group

Description:

The purpose of this intervention was to lead subjects to attend to one's breathing in a non-evaluative manner. Subjects were instructed to sit with a straight posture, closed eyes, and to take a deep, slow breaths every 2-3 minutes.

Treatment:

Other: Saline

Behavioral: Placebo Meditation

Drug: Naloxone

Slow-Breathing Group

Active Comparator group

Description:

A validated (Chalaye et al., 2009) slow breathing training regimen was employed, using fluctuating light, to teach individuals to independently lower their respective respiration rate. Subjects practiced lowering their respiration rates across four, 20 minute sessions.

Treatment:

Other: Saline

Behavioral: Slow-Breathing

Drug: Naloxone