Heritability of Opioid Effects: A Twin Study

NCT00672438 | Completed Results

• 2 other identifiers: SU-04212008-111913018
• Study Type: interventional
• Target: 242
• Locations: 1 country
• Sites: 1

Brief Summary

Proposed twin study will test to what degree inter-individual differences in pain sensitivity and amount of pain relief in response to opioid therapy are inherited or alternatively, are due to environmental factors. This knowledge is important to guide future studies trying to explain such inter-individual differences. For example, finding that differences are largely due to environmental factors would discourage genomic studies and emphasize epidemiological studies.

Conditions

Pain

Outcome Measures

Primary Outcomes (5)

• Heat Pain Threshold

  Degrees Centigrade Heat pain was induced with a thermal sensory analyzer (TSA-II, Medoc Advanced Medical Systems, Durham, North Carolina). A thermode was placed in contact with skin at the volar forearm. Starting at a comfortable temperature, the thermode temperature was increased at a measured rate. Study participants pushed a button of a hand-held device at the onset of pain at which point the thermode immediately reduced the temperature.

  Participants underwent the pain testing measures at training prior to study procedures, at baseline and during each of the infusions.

• Cold Pain Threshold

  Time in seconds Sensitivity to cold-pressor pain was tested by asking subjects to immerse their hand up to the wrist in ice water (1-2 C) continuously re-circulated within a 12-L container with the palm of the hand in full contact with the bottom of the container.They were asked to indicate the onset of pain - reported as pain threshold.

  Participants underwent the pain testing measures at training prior to study procedures, at baseline and during each of the infusions.

• Cold Pain Tolerance

  Time in seconds Sensitivity to cold-pressor pain was tested by asking subjects to immerse their hand up to the wrist in ice water (1-2 C) continuously re-circulated within a 12-L container with the palm of the hand in full contact with the bottom of the container.They were asked to remove their hand from the water bath when it was no longer tolerable - reported as pain tolerance.

  Participants underwent the pain testing measures at training prior to study procedures, at baseline and during each of the infusions.

• Respiratory Rate

  Breaths per minute counted by direct observation and additionally recorded / external electronic monitoring.

  Measured throughout the study session ~ 5 hours

• Transcutaneous Partial Pressure of Carbon Dioxide

  Partial pressure of transcutaneous carbon dioxide (CO2) was measured with aid of a pO2/pCO2-electrode (Perimed Inc., North Royalton, OH) mounted to the anterior chest wall.

  Measured continuously throughout the study session ~ 5 hours

Secondary Outcomes (9)

• Sedation

  The trail making test was performed at training prior to study procedures, at baseline, and during each of the infusions.

• Average Nausea

  At the end of each infusion stage. 2 times total.

• Maximum Nausea

  At the end of each infusion stage. 2 times total.

• Average Pruritis

  At the end of each infusion stage. 2 times total.

• Maximum Pruritis

  At the end of each infusion stage. 2 times total.

Study Arms (2)

Saline placebo infusion

PLACEBO COMPARATOR

Subjects will receive an intravenous infusion of normal saline.

Other: Saline placebo infusion

Alfentanil infusion

EXPERIMENTAL

Subjects will receive an intravenous infusion of alfentanil.

Drug: Alfentanil

Interventions

Alfentanil DRUG

Target controlled intravenous infusion of alfentanil at a plasma concentration of 100ng/ml

Also known as: Alfenta

Alfentanil infusion

Saline placebo infusion OTHER

Intravenous infusion of normal saline

Saline placebo infusion

Eligibility Criteria

• Age: 18 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

Sponsors & Collaborators

• Martin Angst: lead
• SRI International: collaborator

Study Sites (1)

Stanford University School of Medicine

Stanford, California, 94305, United States

Location

MeSH Terms

Conditions

Pain

Interventions

Alfentanil

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Fentanyl; Piperidines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Limitations and Caveats

The study was completed as intended, enrolling 121 twin pairs for a total of 114 evaluable pairs. There are no unexpected adverse events to report.

Results Point of Contact

• Title: Dr. Martin Angst, Professor of Anesthesia
• Organization: Stanford University

ang@stanford.edu

650-498-5109

Study Officials

• Martin S Angst

  Stanford University

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Professor of Anesthesia

Study Record Dates

• First Submitted: May 2, 2008
• First Posted: May 6, 2008
• Study Start: May 1, 2008
• Primary Completion: June 1, 2010
• Study Completion: June 1, 2010
• Last Updated: January 6, 2017
• Results First Posted: July 21, 2016

Record last verified: 2017-01

Locations

US (1)