Gastroesophageal reflux disease (GERD) is defined as a condition of troublesome symptoms and/or complications caused from the reflux of stomach contents . Despite the high morbidity rate at present, the number of GERD patients is still increasing worldwide . Most GERD patients presented esophageal syndromes such as heartburn, chest pain, dysphagia, odynophagia, and so on, though it has recently become clear that not a few latent GERD subjects are suffering from extraesophageal syndromes . Esophageal GERD includes two pathophysiological states: reflux esophagitis (RE, diagnosed by endoscopic observation) and non-erosive reflux disease (NERD, mainly diagnosed on the basis of the upper gastrointestinal symptoms). Most studies reported that NERD patients occupy more than half of all GERD patients [3–5].
Nowadays, it has been the worldwide consensus that the goals of GERD therapy should be based on the improvement of various symptoms and prevention of complications, such as esophageal strictures, gastrointestinal bleeding and Barrett's esophagus [6–9]. Actually, most of the guidelines for GERD emphasize relieving the bothersome symptoms rather than preventing the endoscopic esophageal injury [10–12], probably reflecting the high prevalence of endoscopy-negative cases among GERD patients [4, 5]. Therefore, precise evaluation of GERD symptoms is quite important for not only grasping the patient's disorder but also assessing effectiveness of the therapy. To assess the GERD symptoms, several questionnaires have been proposed, such as QUEST , Manterola's Scale , FSSG (Frequency Scale for the Symptoms of GERD) , Zimmerman's Scale , and so forth. Whereas typical symptoms of GERD are heartburn and regurgitation , it is well known that GERD patients present very diverse symptoms . In the present study, we chose FSSG scoring, as it can evaluate not only the acid-reflux related symptoms but also the dyspeptic symptoms [15, 18].
There have been many studies which examined the relation between GERD (especially reflux esophagitis) and predictive background factors such as age [19, 20], gender [19, 20], body mass index (BMI) , obesity , hiatus hernia , and so on, but large-scale studies focusing on GERD symptoms alone have been very few. Since it is a very common disease affecting millions of people around the globe, it is quite important to clarify the causative lifestyle factors affecting various GERD symptoms. Therefore, one of our aims in this study is to analyze the correlation between GERD symptoms and background variables, especially focused on lifestyle factors.
Another aim of our study is to evaluate the efficacy of proton pump inhibitors (PPI) and histamine H2-receptor antagonists (H2RA), both of which are the most popular drugs used for GERD treatment world-wide. The FSSG scores of PPI users and H2RA users were analyzed in the same univariate and multivariate manner, which would illuminate actual background factors of GERD patients under medical treatment, and also could clarify the efficacy of medication upon habitual antacid users. Through the cross-sectional analysis of the large-scale healthy population, our study should shed light on the pathophysiology of GERD symptoms.