Ninety-Six-Hour Ambulatory Esophageal pH Monitoring in Patients with Refractory Acid Reflux Symptoms Off- and On-Proton Pump Inhibition Therapy and Their Response to Anti-reflux Diet.

backgroundThe proton pump inhibitors (PPIs) are widely prescribed for the treatment of dyspepsia and heartburn. However, their use carries the long-term potential for drug-drug interactions, osteopenia, opportunistic infections, adverse cardiovascular outcomes, and altered gut microbiome. Proper indication for and PPI dose optimization would be clinically beneficial.

aimsExamine the use of endoscopy with esophageal 96-h ambulatory pH monitoring with patients off- and on-PPI, to guide clinicians in prescribing PPI, thereby minimizing inappropriate use, or adverse effects. Specifically, examine (1) the prevalence of normal and abnormal acid exposure time (AET) in PPI users and non-users; (2) the degree, if any, of restrictive diet on AET in the presence or absence of PPI use. We hypothesized that such patients would have inadequate esophageal pH control and that restrictive diet would be beneficial. PATIENTS AND

methodsRetrospective cohort study of consecutive patients presenting with PPI-refractory symptoms of gastroesophageal reflux disease (GERD). All patients underwent an endoscopy with wireless esophageal ambulatory pH monitoring performed either off-PPI or on-PPI therapy for 96 h, following a "liberal diet" for the first 48 h and a "restricted diet" for the latter 48 h of the study. AET was defined as the % time the pH in the distal esophagus was < 4.0; values ≥ 6% per 24 h defined an abnormal AET off-PPI. Control of AET on-PPI was defined as distal esophageal pH < 4 < 1.6% total time. For each patient, the average from the first 2 days (on liberal diet) was considered as the baseline AET and was compared with the average from the latter 2 days (on restricted diet). Depending on the baseline (first 48 h) AET, patients were further divided into 2 groups: those with normal and those with abnormal AET.

resultsWe studied 54 consecutive patients with PPI-refractory GERD symptoms. There were 2 groups: those who underwent pH monitoring off-PPI (n = 32) and those who were studied on-PPI (n = 22). In the off-PPI group, there were 26 women (81%) and 6 men (19%), median age 59 years (range 43-76). In the on-PPI group, there were 16 women (73%) and 6 men (27%), median age 66 years, (range 44-78). Of the 32 patients studied off-PPI, 12 (38%) exhibited abnormal AET (% > 6), while the remaining 20 (62%) had normal AET. Of the 22 patients studied on-PPI, 7 (32%) exhibited abnormal AET (% > 1.6), while 15 (68%) had normal AET. The dietary restriction had a statistically significant impact on reducing and (often normalizing) AET in both PPI users and non-users.

conclusionsTogether with endoscopy, ambulatory 96-h pH monitoring, is feasible and well-tolerated. Most patients (62-68%) with symptomatically PPI-refractory GERD studied either off- or on-PPI, exhibit normal AET. Restrictive diet has a favorable impact on AET in most such patients, but its long-term impact remains unknown.