Oesophageal pH has a power‐law distribution in control and gastro‐oesophageal reflux disease subjects

Abstract

SUMMARYBackground: We are unaware of any solid theoretical or pathophysiological basis for selecting pH 4 or any other pH value to assess oesophageal acid exposure or to define oesophageal reflux episodes. Aim: To examine the frequency of different oesophageal pH values in control and GERD subjects. Methods: Oesophageal pH was measured for 24 h in 57 gastro-oesophageal reflux disease subjects and 26 control subjects. Histograms were constructed using the 21 600 values from each recording and bins of 0.25 pH units.

Continuous distal oesophageal acidification decreases postprandial gastric acidity in healthy human subjects

“…One limitation of this study is that the continuous infusion of 10 m m HCl into the distal oesophagus does not reproduce the physiological conditions with spontaneous gastro‐oesophageal reflux. Typically after a meal, distal oesophageal pH fluctuates between 1.5 and 6.5 instead of being exposed to a constant pH of 2 as in this study 27, 28 . In fact, postprandial oesophageal pH values have a power‐law distribution with pH 2 occurring at a very low frequency 27 .…”

“…Typically after a meal, distal oesophageal pH fluctuates between 1.5 and 6.5 instead of being exposed to a constant pH of 2 as in this study 27, 28 . In fact, postprandial oesophageal pH values have a power‐law distribution with pH 2 occurring at a very low frequency 27 . We chose continuous exposure of the distal oesophagus to 10 m m HCl, however, because we wanted to make sure that we would not miss an effect of oesophageal acidification because of insufficient stimulus.…”

Diagnosis of digestive functional disease by the statistics of continuous monitoring of esophageal acidity

“…In the present project, we apply statistical methods derived from HVR analysis to time series of esophageal acidity (pH continuous monitoring). Previously, degenerations of the digestive rhythm have been identified in patients with GERD [2,3].…”

Oesophageal pH has a power‐law distribution in control and gastro‐oesophageal reflux disease subjects

“…Sirs , It was with great interest that we read the paper by Gardner et al 1 about the frequency distribution of oesophageal pH in health and gastro‐oesophageal reflux disease. The results of the study provide no support for the selection of pH 4 as threshold in the analysis of 24‐h oesophageal pH studies.…”