Fructose Breath-testing in Irritable Bowel Syndrome (IBS)
Condition: Functional Gastrointestinal Disorders; Irritable Bowel Syndrome
MeSH terms: Irritable Bowel Syndrome; Gastrointestinal Diseases; Digestive System Diseases; Syndrome
Study type: Interventional

Summary: 
      Background: Breath testing for food intolerances is becoming routine in patients with
      functional gastrointestinal disorders (FGID). Both FGID and saccharide intolerances (FODMAPs:
      fermentable oligo-, di-, polysaccharide and polyols, e.g. lactose, fructose, sorbitol) are
      common (>10% of any given population) and often respond to dietary modification. The breath
      tests are based on quantification of gas excretion in breath as a sign of malabsorption and
      symptom provocation, but are likely subject to considerable psychological bias. The role of
      expectation and other psychological effects on breath testing has not been reported, but is
      crucial for the validation of these increasingly wide-spread tests with considerable dietary
      and potentially deleterious consequences. Fructose has been shown to result in short term
      pro-inflammatory metabolic responses, but these effects have not been studied as underlying
      causes for intolerance symptoms in fructose intolerant patients with FGID.

      Aim: To investigate the psychological component and the short-term metabolic effects of
      fructose breath testing in patients referred for evaluation of FGID using placebo.
      Additionally, to assess baseline predictors for a positive breath test result.

      Methods: Fructose intolerance (defined by a positive symptom index) and malabsorption
      (defined by increased breath hydrogen/methane concentrations) will be determined in 30
      successive male and female FGID in a single centre using breath-testing. Fructose 35g, given
      double-blind as well as open, a sweet placebo (cyclamate/saccharine; Assugrin®) and a neutral
      (still water) placebo given double-blind will be compared in a randomized, cross-over
      sequence and according to our standardised procedure on four separate study days. Symptoms
      will be recorded using standardised questionnaires and breath concentrations of H2 and CH4
      will be measured during testing on the four study days. Somatisation and psychological
      profiles will be assessed by questionnaires. Blood samples will be obtained before and during
      provocation testing to assess short-term responses to fructose loading by metabolomics.
      Fructose, blinded and open, and placebo responses will be compared and baseline predictors
      for a positive breath tests assessed.
    


Intervention name(s): Open breath test with fructose; Breath test with sweet placebo (Assugrin); Breath test with neutral placebo (still water); Blinded breath test with fructose
Intervention type(s): Procedure; Procedure; Procedure; Procedure
Intervention description(s): Open randomised fructose 35g during breath test; Double-blind randomised breath-testing with sweet placebo (Assugrin); Double-blind randomised breath-testing with neutral placebo; Double-blind randomised fructose 35g during breath test
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Diagnostic
Keywords: Fructose; Irritable Bowel Syndrome; Breath test; Placebo