Table 1.

Exclusion Criteria of Subjects

Exclusion criteria

< 18 years old Measurement of 24-hour impedance-pH monitoring less than 21 hours Administration of proton pump inhibitor and histamine H2 receptor antagonist within last 2 weeks History of upper gastrointestinal surgery Esophageal structure and functional motility disorders (except pathologies related with GERD) Barrett’s esophagus Eosinophilic esophagitis All cancers except nonmelanoma skin cancers Severe or uncontrolled systemic diseases such as chronic obstructive pulmonary disease, coronary artery disease, chronic renal and hepatic disorders, diabetes mellitus Nonsteroidal anti-inflammatory drug or acetylsalicylic acid usage within last week Pregnancy and lactation No appropriate histological samples Unsigned informed consent form

GERD, gastroesophageal reflux disease.