A Prospective Multicenter Study on the Prevalence of Fructose Malabsorption in Patients with Chronic Inflammatory Bowel Disease

Abstract

<b><i>Background and Aims:</i></b> Patients with chronic inflammatory bowel disease (IBD) might have a higher prevalence of fructose malabsorption than healthy controls. This study’s aim was to determine the prevalence and symptom severity of fructose malabsorption in patients with active and inactive IBD. <b><i>Methods:</i></b> The present study was a multicenter noninterventional diagnostic pilot trial. Two hundred fifty-one participants were recruited from 12 outpatient clinics for internal medicine across Germany and from the University of Kiel. Fructose malabsorption was diagnosed by hydrogen breath testing. Patients diagnosed with bacterial overgrowth, non-H₂ producers, and patients who were tested positive for lactose malabsorption were excluded. Gastrointestinal symptoms during breath testing were evaluated using four-point subjective items to determine severity of bloating, abdominal pain, and diarrhea. <b><i>Results:</i></b> Two hundred five patients (45 with active IBD, 80 with IBD in remission, and 81 healthy controls) were analyzed. The number of patients diagnosed with fructose malabsorption – 35/44 (79.6%) in patients with active IBD, 59/80 (73.8%) inactive IBD, and 66/81 (81.5%) in healthy controls – did not differ between the groups (χ² [2, <i>N</i> = 205] = 1.48, <i>p</i> = 0.48). However, abdominal pain was more frequent in patients with active IBD than patients with IBD in remission (<i>z</i> = −2.936, <i>p</i> = 0.010), and diarrhea was more frequent in patients with active IBD than in healthy controls (<i>z</i> = 2.489, <i>p</i> = 0.038). <b><i>Conclusions:</i></b> Fructose malabsorption is not more common among patients with IBD than healthy subjects. However, the greater prevalence of patient-reported symptoms among patients with IBD may be of pathological and therapeutic relevance.