Prevalence of overlaps between GERD, FD and IBS and impact on health-related quality of life

Objective: Gastroesophageal reflux disease (GERD), functional dyspepsia (FD), and irritable bowel syndrome (IBS) are common, and have negative impacts on health-related quality of life (HR-QOL). Several studies demonstrated a significant overlap between two of these three diseases. The purpose of this study was to examine the prevalence of GERD, FD, and IBS, their overlap rates, and HR-QOL for each disease and each overlap compared with healthy controls in the Japanese general population. Methods: We performed a cross-sectional study of Japanese workers who visited a clinic for a routine health check-up, and asked them to fill out a self-report questionnaire. Prevalence and overlap rate of GERD defined as heartburn and/or acid regurgitation at least weekly, FD and IBS based on Rome III criteria, and HR-QOL by SF-8 were examined. Results: Of the 2680 eligible subjects, 207 (7.7%) were diagnosed as having GERD, 269 (10.0%) as FD, and 381 (14.2%) as IBS. Overlaps were found in 46.9% in GERD, 47.6% in FD, and 34.4% in IBS. Prevalence of overlaps in subjects with IBS was significantly lower compared with those among GERD or FD. Sufferers from GERD, FD, or IBS reported significantly poorer HR-QOL across all domains compared with controls. Overlaps significantly worsened HR-QOL in most domains except in the 'role emotional' domain. HR-QOL was particularly poor in the physical component summary for overlapping GERD and in the mental component summary for overlapping IBS. Conclusion: Overlaps among GERD, FD and IBS were common and worsened HR-QOL in Japanese general population.