Study of Endogenous Inhibitory Modulation During Gastric and Somatic Stimulation

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

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Functional Dyspepsia

Age range

18 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

National University Hospital, Singapore

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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

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.

Treatment and study plan

gastric capsaicin with heterotopic stimulation/ distraction

Procedure

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.

Primary outcomes

Differences between healthy controls and FD subjects in visceral pain scores.

Time frame: within 2 hours of Capsaicin challenge

Sponsors and collaborators

Lead sponsor

National University Hospital, Singapore

Other

Collaborators

NMRC, Singapore

Registry information

Official study title

Activation of Endogenous Inhibitory Modulation During Gastric and Somatic Stimulation in Functional Dyspepsia Patients and Healthy Controls

Important dates

Study start: 2008
Primary completion: 2011
Study completion: 2012
First posted: Jun 9, 2008
Registry last updated: Jan 7, 2014

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.

Completed