BACKGROUND/AIMS: There have been few studies on the efficacy of proton pump inhibitors and the doses required to treat dyspeptic symptoms observed in clinical practice. The aim of this study was to compare the efficacy of different doses of omeprazole and different administration methods in Helicobacter pylori-negative, dyspeptic patients. METHODS: Patients with chronic upper abdominal symptoms within the previous 3 months were randomly divided into three groups: a daily, omeprazole 20 mg treatment group (OPZ20, n=61); a daily, omeprazole 10 mg treatment group (OPZ10, n=72); and an on-demand omeprazole 20 mg treatment group (on-demand, n=62). After 4 weeks of administration of the drug, symptom improvement rates were evaluated based on the Overall Global Severity score. RESULTS: The rates of symptom improvement after 4 weeks of treatment were 65.6% (40/61) in the OPZ20 group, 47.2% (34/72) in the OPZ10 group, and 50.0% (31/62) in the on-demand group. The OPZ20 group exhibited a significantly higher improvement rate (p=0.034) than the OPZ10 group. The OPZ20 group had significant improvements in regurgitation, postprandial fullness, vomiting, and bloating compared with the OPZ10 group. CONCLUSIONS: Daily treatment with 20 mg of omeprazole was efficient in treating upper abdominal symptoms. Trial registration: ClinicalTrials.gov, number UMIN000002621.
Dyspepsia ; Helicobacter ; Humans ; Japan ; Omeprazole ; Primary Health Care ; Proton Pump Inhibitors ; Proton Pumps ; Protons ; Vomiting

Background/Aims: Although risk factors of reflux esophagitis (RE) have been investigated in numerous cross-sectional studies, little is known about predictive factors associated with future onset of RE. We investigated time courses of clinical parameters before RE onset by a longitudinal case-control study using health checkup records. Methods: We used health checkup records between April 2004 and March 2014 at 9 institutions in Japan. A multivariate logistic regression analysis was performed to evaluate associations of baseline clinical parameters with RE. The time courses of the clinical parameters of RE subjects were compared with those of non-RE subjects by the mixed-effects models for repeated measures analysis or longitudinal multivariate logistic analysis. Results: Initial data were obtained from 230 056 individuals, and 2066 RE subjects and 4132 non-RE subjects were finally included in the analysis. Body mass index, alanine aminotransferase, smoking, acid reflux symptoms, hiatal hernia, and absence of atrophic gastritis at baseline were independently associated with RE. The time courses of body mass index, fasting blood sugar, triglyceride, aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transpeptidase, percentages of acid reflux symptoms, feeling of fullness, and hiatal hernia in the RE group were significantly worse than in the non-RE group. Conclusions The RE group displayed a greater worsening of the clinical parameters associated with lifestyle diseases, including obesity, diabetes, hyperlipidemia, and fatty liver for 5 years before RE onset compared with the non-RE group. These results suggest that RE is a lifestyle disease and thus lifestyle guidance to at-risk person may help to prevent RE onset.