Gastrointestinal peptides and small-bowel hypomotility are possible causes for fasting and postprandial symptoms in active Crohn’s disease

Abstract

Crohn's disease (CD) patients suffer postprandial aversive symptoms, which can lead to anorexia and malnutrition. Changes in the regulation of gut hormones and gut dysmotility are believed to play a role. This study aimed to investigate small-bowel motility and gut peptide responses to a standard test meal in CD by using MRI. We studied 15 CD patients with active disease (age 36±3 y; BMI 26±1 kg/m 2) and 20 healthy volunteers (HVs; age 31±3 years; BMI 24±1 kg/m 2). They underwent baseline and postprandial MRI scans, symptom questionnaires, and blood sampling following a 400-g soup meal (204 kcal). Small-bowel motility, other MRI parameters, and glucagon-like peptide-1 (GLP-1), polypeptide YY (PYY), and cholecystokinin peptides were measured. Data are presented as means±SEMs. HVs had significantly higher fasting motility indexes [106±13 arbitrary units (a.u.)], compared with CD participants (70±8 a.u.; P≤0.05). Postprandial small-bowel water content showed a significant time by group interaction (P<0.05), with CD participants showing higher levels from 210 min postprandially. Fasting concentrations of GLP-1 and PYY were significantly greater in CD participants, compared with HVs [GLP-1, CD 50±8 µg/mL versus HV 13±3 µg/mL (P≤0.0001); PYY, CD 236±16 pg/mL versus HV 118±12 pg/mL (P≤0.0001)]. The meal challenge induced a significant postprandial increase in aversive symptom scores (fullness, distention, bloating, abdominal pain, and sickness) in CD participants compared with HVs (P≤0.05). The decrease in fasting small-bowel motility noted in CD participants can be ascribed to the increased fasting gut peptides. A better understanding of the etiology of aversive symptoms in CD will facilitate identification of better therapeutic targets to improve nutritional status. This trial was registered at clinicaltrials.gov as NCT03052465.