Risk factors of gastroesophageal reflux disease: methodology and first epidemiological results of the ProGERD study

Objective We describe the design and report the first results of the Progression of Gastroesophageal Reflux Disease (ProGERD) study, to our knowledge the largest prospective study of GERD patients. Study Design and Setting Patients were recruited at 1,253 centers in Germany, Austria, and Switzerland. Following an assessment of medical history, all patients were endoscoped and received esomeprazole for 2 to 8 weeks before entering the 5-year observational phase. Results A total of 6,215 patients (53% male, age 54±14) were included. Of these patients, 46% reported at least daily symptoms, 15% were unable to work at least once during the prior year, and 71% had visited a physician due to reflux symptoms. Barrett's esophagus (BE) was found in 11% of our GERD patients. In polychotomous regression analysis, the main factors related to the occurrence of the three GERD subgroups (nonerosive, erosive disease, and BE) were age, gender, duration of GERD, body mass index (BMI), smoking, and previous PPI use. Factors associated with longer disease duration were increasing age, male gender, BMI, increasing symptom severity, presence of erosive GERD or BE, positive family history, and smoking. Conclusion The findings indicate that GERD is a great burden for patients, and has significant socioeconomic implications. The long-term follow-up period with further endoscopic and histologic evaluations, will help further our understanding of the natural course of the disease.