Psychophysiological study of functional dyspepsia

Functional dyspepsia (FD) is a common disorder. Its etiology is insufficiently known. Specific treatment is often lacking. This thesis investigates the following questions: 1) do FD patients have different psychological symptoms and personality compared with a matched healthy control group?, 2) do the two groups have different levels or patterns of plasma hormones in a psychophysiological experiment?, 3) how do gastrointestinal and psychological symptoms develop over time as measured in a seven-year follow-up?, and 4) do any of the hormones in the first study predict symptom development between the two studies?

25 patients (12 men, 13 women), between 24 and 50 years old, were compare pairwise with community control subjects. Peptic ulcer and other organic diseases were excluded. Clinical symptoms, personality and psychosocial data were studied. In an experiment with different provocations, plasma was sampled for biochemical analyses. 24 of the patients and 22 of the control subjects participated in the follow-up study seven years later.

4 patients and 3 control subjects had a positive titre for Helicobacter pylori. Significant results: In Karolinska Scales of Personality, the patient group scored lower detachment than the control group. During a 15 min stress interview, with the aim to elicit anxiety in the subject, plasma gastrin and prolactin increased in both groups. Cholecystokinin increased in the patients but not in the control subjects. Somatostatin correlated positively with dyspeptic symptoms. The prolactin level was lower in the patient group than in the control group. Motilin was lower in subjects with a higher level of indigestion symptoms. Increase of motilin correlated with increase of joyfulness during the test. There was a negative correlation between cortisol and diarrhoea symptoms. In the follow-up study, somatostatin predicted continuous abdominal pain symptoms. Within the patient group, low cortisol correlated and low motilin tended to correlate with a higher degree of diarrhoea symptoms. Neuropeptide Y had no relation to gastrointestinal symptoms.