Twice-daily proton pump inhibitor therapy does not decrease the frequency of reflux episodes during nocturnal recumbency in patients with refractory GERD: analysis of 200 patients using multichannel intraluminal impedance-pH testing

Over half of patients with gastroesophageal reflux disease (GERD) report nocturnal symptoms. Proton pump inhibitors (PPIs) are the main medications used to treat GERD. Multichannel intraluminal impedance with pH (MII-pH) monitoring is the most sensitive method for detection and characterization of GERD. The aim of this study was to assess and compare reflux frequency in patients with refractory GERD symptoms on and off PPI therapy during the nocturnal recumbent period, as assessed by MII-pH testing. We analyzed 24-hour MII-pH studies performed in 200 patients monitored either on twice-daily (n = 100) or off (n = 100) PPI therapy. Demographic analysis of the on-therapy group revealed a mean age of 52 years (2478 years) with 37% males, and the off-therapy group revealed a mean age of 49 years (1884 years) with 40% males. All studies were interpreted to assess and characterize the number of acid and nonacid reflux episodes in the nocturnal recumbent period identified by each patient on an overnight recorder (Zephyr, Sandhill Scientific, Inc., Highlands Ranch, CO, USA). The nocturnal recumbent period was the period documented by patients during which they lie in the recumbent period at night to sleep with average periods lasting 456 and 453 minutes for patients on and off PPI therapy. There were more mean recumbent reflux episodes in the on-therapy group in comparison with the off-therapy group (3.76 mean reflux episodes [mre] per patient in the recumbent vs. 2.82 mre); the difference was not statistically significant (P = 0.187). When the reflux events are classified into acid and non-acid reflux episodes, the relative occurrence of acid reflux events is less in the on-therapy group (P = 0.047), while the off-therapy group have fewer nonacid reflux episodes (P = 0.003). PPIs decrease the acidity of esophageal refluxate but do not decrease the relative frequency of reflux episodes in the recumbent position in patients with refractory GERD despite twice-a-day treatment with PPI therapy. The explanation for the finding of numerically increased, although not statistically significant, amount of reflux episodes in the PPI treatment group in this study, and previous studies is unclear and warrants further evaluation.