Objective: Functional dyspepsia (FD) is a syndrome in which several causes are probably involved. Our aim was to investigate the association between specific dyspeptic symptoms and Helicobacter pylori infection or delayed gastric emptying.
Methods: Nine hundred thirty-five consecutive outpatients with unexplained dyspepsia were studied. After appropriate investigation, 304 patients were diagnosed as affected by chronic FD and were tested for H. pylori infection and gastric emptying of solids by means of 13C-urea and 13C-octanoic acid breath tests. Four dyspeptic symptoms (epigastric pain or burning, postprandial fullness, nausea, and vomiting) were scored as absent, mild, moderate, or severe (0-3) according to their influence on the patients' activities. Symptoms of irritable bowel syndrome and gastroesophageal reflux disease were also assessed. On the basis of symptom scores, three groups were identified: "prevalent pain" (10.5%), "prevalent discomfort" (32.6 %), and "unclassifiable" dyspepsia (56.9%).
Results: Of the 304 patients with FD, 208 (68.4 %) were H. pylori-positive on urea breath test. Gastric emptying was delayed in 99 subjects (32.6%). Patients with "prevalent pain" were infected significantly more often (81.2% vs 59.6%; p = 0.026) and less frequently had delayed gastric emptying (6.2% vs 40.4%; p = 0.0001) than those with "prevalent discomfort." H. pylori infection was independently associated with age > or =40 yr and epigastric pain or burning > or =2 (odds ratio [OR] and 95% confidence interval [CI] 4.09 [2.39-7.00] and 1.70 [1.04-2.77], respectively). Delayed gastric emptying was independently associated with a cumulative score > or =6 for postprandial fullness, nausea, and vomiting (OR [95% CI]: 3.13 [1.06-9.18]). H. pylori status had no influence on gastric emptying. Logistic regression analysis showed that delayed gastric emptying, female sex, and concomitant symptoms of inflammatory bowel syndrome were independently associated with a cumulative score > or =6 for postprandial fullness, nausea, and vomiting (p = 0.0281, p = 0.0387, and p = 0.0316, respectively). Moreover, concomitant symptoms of gastroesophageal reflux disease, female sex, and H. pylori infection were independently associated with epigastric pain or burning > or =2 (p = 0.002, p = 0.0001, and p = 0.0875, respectively).
Conclusions: Two subsets of FD patients have been identified on the basis of symptoms. One subgroup is mainly characterized by "prevalent pain," H. pylori infection, and normal gastric emptying; the other one demonstrates "prevalent discomfort" and delayed gastric emptying. These findings shed some light on possible etiopathogenetic mechanisms of FD.