Pain Inhibition and Facilitation in Post Partum WomenNCT01843517
Endogenous Pain Facilitation and Inhibition in Postpartum Women
An observational study of Pain Inhibition and Facilitation in Post Partum Women, run by Wake Forest University at 1 site in United States.
Trial summary
This study seeks to further understand these three observations - (1) that the time period surrounding childbirth accelerates recovery from pain after injury (2) that this likely reflects dampened facilitating mechanisms and exaggerated inhibitory mechanisms, and (3) that stress may interfere with this protection. Read more about this study
- Who is it for?
- Ages 18 years and older, women onlyHealthy volunteers can take part
- Conditions the study is for
- Pain Inhibition and Facilitation in Post Partum Women
- How many people
- 80 participants
- Where
- 1 siteUnited States
- Study dates
- Apr 2013to 5 Dec 2017
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- Women only
- Healthy volunteers accepted
- Adult, Older adult
Study population: Healthy women 10-14 days postpartum following term vaginal delivery, who are breast feeding and age- and race- matched healthy, nonpregnant women, either nulliparous or at least 1 year beyond delivery.
Who may be able to join
- female
- 10-14 days postpartum, term vaginal delivery
- breastfeeding (postpartum women)
- health non-pregnant female (nulliparous or at least 1 year beyond delivery)
Who cannot join
- Allergy to chili peppers
- pregnant
- pain medication (narcotic or non-narcotic) within 4 hours of study visit Average pain in the 24 hours preceding the study visit >3. Postpartum women that score >13 on the Edinburgh Postnatal Depression Scale
Trial locations and contacts
1 site in 1 country.
United States1 site
Wake Forest Baptist Medical Center
Winston-Salem, North Carolina, 27157
About this study
This study seeks to further understand these three observations - (1) that the time period surrounding childbirth accelerates recovery from pain after injury (2) that this likely reflects dampened facilitating mechanisms and exaggerated inhibitory mechanisms, and (3) that stress may interfere with this protection. In this study the investigators will compare women within 2 weeks of delivery to age matched controls and anticipate that pain inhibition is increased after delivery, pain facilitation is decreased, and that there is a relationship between these pain responses and the degree of pre-existing stress.
Read the detailed description
Nearly half of the world's population experiences labor and delivery processes which are associated with microscopic or gross tissue injury to the mother. Since this experience is widespread and occurs relatively early in life, the psychosocial, medical, and financial consequences of chronic pain following childbirth could be enormous. Surprisingly, previous studies with long term follow up of new mothers have included pain as a secondary measure and / or have focused on prevalence of pain without determining whether pain predated delivery or even pregnancy itself. The investigators recently performed a long term follow up study of over 1,200 women, and noted that pain which began during the childbirth itself was surprisingly rare in comparison to other physical injuries. Additionally, two central factors hypothesized to confer risk of chronic pain after other injuries including surgery, pre-dating chronic pain and degree of tissue and nerve injury, contributed minimally to the acute and sub-acute pain after childbirth. These two observations, low incidence of chronic pain and minimal effect of degree of tissue injury and history of chronic pain on sub-acute pain, point towards a potential protective effect of pregnancy or delivery on the response to physical injury.
- Keywords
- Pain, Facilitation, Inhibition, Oxytocin, Postpartum
- Medical subject headings
- Pain, Inhibition, Psychological
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| endogenous pain facilitation | Pain facilitation is studied by a simple test of applying over the counter capsaicin cream to the skin for only 30 min, then removing it and heating the skin to a non-noxious temperature. | |
| endogenous pain inhibition | Pain inhibition is studied by a simple test of mild pain on one area of the body reducing response to a pain stimulus in another area. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Area of hyperalgesia will be the primary outcome measure
Hyperalgesia and allodynia on the skin of the forearm will be established by heating the forearm with a 4 cm2 Peltier controlled thermode (TSA®) to 45 degrees Celsius for 5 minutes. The investigators will then apply topical capsaicin (0.075% cream, Bioglan Pharmaceuticals) under an occlusive dressing at the same site as the thermal probe for 30 minutes. 40 minutes after removal of the capsaicin cream the site will be heated to 40 degrees Celsius for 5 minutes (rekindling) following the end of capsaicin application. The investigators will test skin sensations with the filament and cotton wisp after this heating.
Measured: 40 minutes post capsaicin application
Percent reduction in degree of pain to the 49 degrees Celsius stimulus during the time the foot is immersed in the cold water
Conditioned pain modulation will be induced by placing a foot in a container of circulating water maintained at 10 degrees Celsius for 90 seconds. Thirty seconds after the foot is placed into container of circulating water, the stimulus response to heat on the contralateral forearm will be measured using a 49 degrees Celsius stimulus for 5 seconds. The foot will then be withdrawn and warmed with warm blankets. The stimulus response to heat stimuli on the arm will be measured 5 and 15 min thereafter.
Measured: 15 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Apr 2013 (estimated)
- Study startApr 2013
- Primary completion5 Dec 2017
- Study completion5 Dec 2017
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Pain Inhibition and Facilitation in Post Partum WomenStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 80 participants (actual)
Sponsor and investigators
- Lead sponsor
- Wake Forest University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- James C. Eisenach, MD, Principal investigator, Wake Forest University Health Sciences
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01843517
- Sponsor's protocol ID
- IRB00022603
- Status last verified
- Dec 2017
- First submitted
- 25 Apr 2013
- Last updated
- 19 Dec 2017
- Results posted
- No
- Data monitoring committee
- No
Publications
Pan PH, Tonidandel AM, Aschenbrenner CA, Houle TT, Harris LC, Eisenach JC. Predicting acute pain after cesarean delivery using three simple questions. Anesthesiology. 2013 May;118(5):1170-9. doi: 10.1097/ALN.0b013e31828e156f.
PubMed 23485992Street LM, Harris L, Curry RS, Eisenach JC. Capsaicin-induced pain and sensitisation in the postpartum period. Br J Anaesth. 2019 Jan;122(1):103-110. doi: 10.1016/j.bja.2018.09.026. Epub 2018 Nov 16.
PubMed 30579387
Study at a glance
From the registry record, last updated by the sponsor on 19 Dec 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Endogenous Pain Facilitation and Inhibition in Postpartum Women
- ClinicalTrials.gov ID
- NCT01843517
- Acronym / sponsor ID
- IRB00022603
- Keywords
- Pain, Facilitation, Inhibition, Oxytocin, Postpartum
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 80 participants (actual)
- Lead sponsor
- Wake Forest UniversityUniversity, hospital or other
- Study start
- Apr 2013
- Primary completion
- 5 Dec 2017 (actual)
- Study completion
- 5 Dec 2017 (actual)
- First posted
- 30 Apr 2013 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study seeks to further understand these three observations - (1) that the time period surrounding childbirth accelerates recovery from pain after injury (2) that this likely reflects dampened facilitating mechanisms and exaggerated inhibitory mechanisms, and (3) that stress may interfere with this protection. In this study the investigators will compare women within 2 weeks of delivery to age matched controls and anticipate that pain inhibition is increased after delivery, pain facilitation is decreased, and that there is a relationship between these pain responses and the degree of pre-existing stress.
Detailed description
Nearly half of the world's population experiences labor and delivery processes which are associated with microscopic or gross tissue injury to the mother. Since this experience is widespread and occurs relatively early in life, the psychosocial, medical, and financial consequences of chronic pain following childbirth could be enormous. Surprisingly, previous studies with long term follow up of new mothers have included pain as a secondary measure and / or have focused on prevalence of pain without determining whether pain predated delivery or even pregnancy itself. The investigators recently performed a long term follow up study of over 1,200 women, and noted that pain which began during the childbirth itself was surprisingly rare in comparison to other physical injuries. Additionally, two central factors hypothesized to confer risk of chronic pain after other injuries including surgery, pre-dating chronic pain and degree of tissue and nerve injury, contributed minimally to the acute and sub-acute pain after childbirth. These two observations, low incidence of chronic pain and minimal effect of degree of tissue injury and history of chronic pain on sub-acute pain, point towards a potential protective effect of pregnancy or delivery on the response to physical injury.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| endogenous pain facilitation | – | –Pain facilitation is studied by a simple test of applying over the counter capsaicin cream to the skin for only 30 min, then removing it and heating the skin to a non-noxious temperature. |
| endogenous pain inhibition | – | –Pain inhibition is studied by a simple test of mild pain on one area of the body reducing response to a pain stimulus in another area. |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- Healthy women 10-14 days postpartum following term vaginal delivery, who are breast feeding and age- and race- matched healthy, nonpregnant women, either nulliparous or at least 1 year beyond delivery.
Key inclusion criteria (4 listed)
- female
- 10-14 days postpartum, term vaginal delivery
- breastfeeding (postpartum women)
- health non-pregnant female (nulliparous or at least 1 year beyond delivery)
Key exclusion criteria (3 listed)
- Allergy to chili peppers
- pregnant
- pain medication (narcotic or non-narcotic) within 4 hours of study visit Average pain in the 24 hours preceding the study visit >3. Postpartum women that score >13 on the Edinburgh Postnatal Depression Scale
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Area of hyperalgesia will be the primary outcome measure
Time frame: 40 minutes post capsaicin application
Hyperalgesia and allodynia on the skin of the forearm will be established by heating the forearm with a 4 cm2 Peltier controlled thermode (TSA®) to 45 degrees Celsius for 5 minutes. The investigators will then apply topical capsaicin (0.075% cream, Bioglan Pharmaceuticals) under an occlusive dressing at the same site as the thermal probe for 30 minutes. 40 minutes after removal of the capsaicin cream the site will be heated to 40 degrees Celsius for 5 minutes (rekindling) following the end of capsaicin application. The investigators will test skin sensations with the filament and cotton wisp after this heating.
Percent reduction in degree of pain to the 49 degrees Celsius stimulus during the time the foot is immersed in the cold water
Time frame: 15 minutes
Conditioned pain modulation will be induced by placing a foot in a container of circulating water maintained at 10 degrees Celsius for 90 seconds. Thirty seconds after the foot is placed into container of circulating water, the stimulus response to heat on the contralateral forearm will be measured using a 49 degrees Celsius stimulus for 5 seconds. The foot will then be withdrawn and warmed with warm blankets. The stimulus response to heat stimuli on the arm will be measured 5 and 15 min thereafter.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 Dec 2017.
- Background: PubMed 23485992Pan PH, Tonidandel AM, Aschenbrenner CA, Houle TT, Harris LC, Eisenach JC. Predicting acute pain after cesarean delivery using three simple questions. Anesthesiology. 2013 May;118(5):1170-9. doi: 10.1097/ALN.0b013e31828e156f.
- Derived from this study: PubMed 30579387Street LM, Harris L, Curry RS, Eisenach JC. Capsaicin-induced pain and sensitisation in the postpartum period. Br J Anaesth. 2019 Jan;122(1):103-110. doi: 10.1016/j.bja.2018.09.026. Epub 2018 Nov 16.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
James C. Eisenach, MD principal investigator
Wake Forest University Health Sciences
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Pain Inhibition and Facilitation in Post Partum Women, run by Wake Forest University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 19 Dec 2017. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Area of hyperalgesia will be the primary outcome measure (time frame: 40 minutes post capsaicin application). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01843517, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Dec 2017.