1,2 In recent years, several studies have uncovered a significant proportion of patients with reflux esophagitis but with no symptoms. In the well conducted, population-based, Kalixanda study from Sweden, for example, up to 36.8% of patients with erosive esophagitis had no symptoms.3 MAPK inhibitor Other studies from the Asian Pacific region have shown a prevalence of asymptomatic reflux esophagitis ranging from 26.4% to 35.0% (Table 1).3–7 In this issue of the Journal of Gastroenterology and Hepatology, Cho and colleagues from Korea, in a survey of over 5000 patients undergoing health-screening gastroscopy, found that 145 of 320 (45.3%) patients with erosive esophagitis

were asymptomatic.7 This is indeed a large proportion of patients who have “silent GERD”. In another endoscopy-based study, Ho et al. found that 33.9% of 186 patients with erosive esophagitis had no typical symptoms of heartburn

and acid regurgitation. Instead these patients had predominant complaints of “wind” and abdominal distension.8 Clearly, the problem could be one of interpretation of symptoms. It has long been known that many Asian patients do not exactly understand the meaning of heartburn and acid SB203580 regurgitation9 and there is a large overlap between reflux and dyspeptic symptoms.10 Furthermore, non-cardiac chest pains, for example, have often been considered in the Asia–Pacific region to be a manifestation of GERD and many patients with non-cardiac chest pains have been shown to have underlying MCE GERD.10 This notwithstanding, silent GERD is now a well-recognized entity. Fass and Dickman11 have defined silent GERD as the presence of esophageal mucosal injury that is typical of GERD (erosions, peptic ulceration and Barrett’s esophagus) during upper gastrointestinal endoscopy in individuals who lack typical or atypical extra-esophageal manifestations of GERD. The ramifications of such a “disease” are huge. The list of reflux-related diseases caused by silent disease include: refractory asthma, persistent laryngopharyngitis, poor sleep, dental caries, Barrett’s esophagus

and, particularly in children, unexplained asthma and recurrent pneumonia.11 Of practical concern is the screening for Barrett’s esophagus. Currently, only patients with symptomatic GERD are screened for Barrett’s esophagus. How do you screen for a disease without symptoms? The whole adult population would require evaluation and this is clearly a monumental if not impossible task. Although Barrett’s esophagus and Barrett’s associated adenocarcinoma are still uncommon in the Asia–Pacific region, this may change with the rapid emergence of GERD in the region.9 What factors determine or predict silent reflux disease? In this study, Cho et al.7 identified older age and male sex as predictive factors. Nozu and Komiyama5 and Wang et al.6 also identified male sex as a predictive factor for silent esophagitis.