Study of Endogenous Inhibitory Modulation During Gastric and Somatic Stimulation

This study has been completed.
Sponsor:
Collaborator:
NMRC, Singapore
Information provided by (Responsible Party):
Medicine, National University Hospital, Singapore
ClinicalTrials.gov Identifier:
NCT00693407
First received: June 5, 2008
Last updated: January 6, 2014
Last verified: January 2014
  Purpose

Visceral hypersensitivity as evidence of central sensory sensitization is evident in many patients with functional disorders such as functional dyspepsia (FD) and irritable bowel syndrome (IBS). We recently demonstrated both somatic hypersensitivity and abnormal endogenous pain modulation in IBS, both of which indicate central sensitization as a crucial mechanism in IBS. Endogenous pain mechanisms regulate, fine-tune and integrate sensory and homeostatic, including neuroendocrine, immune, motor and autonomic nervous system processes. Hitherto, no studies have investigated the role endogenous pain modulation in FD. Abnormal modulation could explain several of the symptom complexes associated with FD and provide a rationale for exploration of new treatments.

The current study was designed to

  1. investigate the gastric sensitivity in FD patients and healthy controls during gastric capsaicin stimulation
  2. assess the endogenous pain inhibitory modulation system in FD patients and healthy controls during heterotopic stimulation

Condition Intervention
Functional Dyspepsia
Procedure: gastric capsaicin with heterotopic stimulation/ distraction

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Diagnostic
Official Title: Activation of Endogenous Inhibitory Modulation During Gastric and Somatic Stimulation in Functional Dyspepsia Patients and Healthy Controls

Resource links provided by NLM:


Further study details as provided by National University Hospital, Singapore:

Primary Outcome Measures:
  • Differences between healthy controls and FD subjects in visceral pain scores. [ Time Frame: within 2 hours of Capsaicin challenge ] [ Designated as safety issue: No ]

Enrollment: 80
Study Start Date: September 2008
Study Completion Date: September 2012
Primary Completion Date: September 2011 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1, FD patients
Eighty male and female FD patients according to Rome III criteria (Drossman, 2006), aged 18 to 70 years, will be recruited from primary and secondary care via advertisements and our referral networks
Procedure: gastric capsaicin with heterotopic stimulation/ distraction
The subjects are randomized to swallow either a capsaicin 0.50mg capsule or an identical placebo capsule with 100ml of water If after 15 minutes pain scores do not reach a minimum level of 30, a further double-blinded capsule of the same content will be swallowed with 100ml of water. This is repeated to a maximum of 8 capusles until pain with VAS >30 is reported.
Experimental: 2,Healthy controls
Forty male and female healthy volunteers, aged 18 to 70 years without any gastrointestinal pathology or history of significant abdominal pain, bowel disorders, bloating or discomfort during the last 3 months will be recruited.
Procedure: gastric capsaicin with heterotopic stimulation/ distraction
The subjects are randomized to swallow either a capsaicin 0.50mg capsule or an identical placebo capsule with 100ml of water If after 15 minutes pain scores do not reach a minimum level of 30, a further double-blinded capsule of the same content will be swallowed with 100ml of water. This is repeated to a maximum of 8 capusles until pain with VAS >30 is reported.

  Eligibility

Ages Eligible for Study:   18 Years to 70 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

FD patients:

  • Eighty male and female FD patients according to Rome III criteria (Drossman, 2006), aged 18 to 70 years, will be recruited from primary and secondary care via advertisements and our referral networks.
  • FD discomfort or pain should be the most prominent symptom.
  • Patients must have been off all FD and analgesic medication and any drugs potentially influencing sensory function for at least two weeks before study start and be able to remain off such medication for the duration of the study period.

Healthy controls:

  • Forty male and female healthy volunteers, aged 18 to 70 years without any gastrointestinal pathology or history of significant abdominal pain, bowel disorders, bloating or discomfort during the last 3 months will be recruited.

Exclusion Criteria:

Exclusion criteria for both FD patients and healthy controls:

  • Organic gastrointestinal or other significant systemic disease, including cardiovascular, dermatological, psychiatric, neurological and endocrine diseases. Patients with peptic ulcer scars are also excluded.
  • Chronic or acute pain, except related to other functional syndromes (irritable bowel syndrome, chronic pelvic pain, fibromyalgia, migraine).
  • H. pylori positive.
  • Abdominal surgery, including gastric resection or cholecystectomy (except appendectomy)
  • History of brain disease or brain surgery.
  • Ongoing treatment with any drugs or need for drugs (or complementary medication) within last 14 days.
  • Treatment with any investigational drug during the preceding 30 days.
  • Ingestion of spicy, chilli pepper containing meal, or use of capsaicin skin cream in last 48 hours before start of study or any study day.
  • Pregnancy or lactation.
  • No written informed consent obtained from subject.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00693407

Locations
Singapore
National University Hospital
Singapore, Singapore, 119074
National University of Singapore
Singapore, Singapore, 119742
Sponsors and Collaborators
National University Hospital, Singapore
NMRC, Singapore
  More Information

No publications provided

Responsible Party: Medicine, National University Hospital, Singapore
ClinicalTrials.gov Identifier: NCT00693407     History of Changes
Other Study ID Numbers: D/07/088
Study First Received: June 5, 2008
Last Updated: January 6, 2014
Health Authority: Singapore: Domain Specific Review Boards

Additional relevant MeSH terms:
Dyspepsia
Signs and Symptoms, Digestive
Signs and Symptoms
Capsaicin
Antipruritics
Dermatologic Agents
Therapeutic Uses
Pharmacologic Actions
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs

ClinicalTrials.gov processed this record on September 18, 2014