Functional Heartburn in a Non-Disease

Abstract

Purpose: Functional heartburn refers to patients with heartburn but normal 24-hour esophageal acid exposure, and these patients are believed to have increased esophageal sensitivity to normal acid exposure. We considered the possibility that patients with functional heartburn might have another explanation for their heartburn. The aim of our analyses was to determine the prevalence of pathologic esophageal reflux in GERD subjects during different times of the day. Methods: Esophageal pH was recorded for 24 hours in 57 subjects with GERD, 11 with NERD, and 26 normal subjects. GERD subjects reported heartburn at least 4 times/week for at least 6 months. NERD reported at least 5 episodes of heartburn during the last 7 days of a 14-day run-in period and were documented to have no erosive esophagitis on UGI endoscopy. The postprandial and nocturnal periods were 900–2200 and 2200–900, respectively. Results: Receiver operator characteristic (ROC) analyses of results for integrated esophageal acidity from normal and GERD subjects showed that pathologic integrated esophageal acidity (mmol.hr/L) was defined as 24-hour >8.1; postprandial >1.85, and nocturnal >6.8. In the present study, the prevalence (95% CI) of pathologic 24-hour esophageal reflux for GERD subjects was 72% (60, 84). The prevalence of pathologic postprandial esophageal reflux was 93% (87, 99), and of pathologic nocturnal reflux was 42% (28, 56). The prevalence of pathologic 24-hour, postprandial and nocturnal esophageal reflux for 11 NERD subjects was 64% (34, 94), 91% (73,109), and 27% (1, 53), respectively. In subjects with normal 24-hour esophageal reflux, the prevalence of pathologic postprandial esophageal reflux was GERD - 77% (59, 95), and NERD - 75% (31,119). Conclusions: The present results indicate that nearly all GERD subjects with heartburn have pathologic postprandial esophageal reflux, and this abnormality can account for heartburn in most GERD or NERD subjects with normal 24-hour esophageal acidity. Thus, there is no need to postulate increased esophageal acid sensitivity in GERD or NERD subjects with normal 24-hour esophageal acid exposure or to refer to them as having “functional heartburn”.