Background: The data pertaining to esophageal acid exposure during multichannel intraluminal impedance-pH testing (MII-pH) may be analyzed by using all pH drops (simulating traditional pH-monitoring) or analyzing only pH drops associated with impedance changes. It is unknown whether the acid exposure measurements would differ between these methods in a group of symptomatic patients. Methods: We retrospectively evaluated MII-pH studies of patients from 2008 to 2013. Studies were re-analyzed so that acid measurements were obtained in two methods: 1. Creating nonmealtime pH measurements related to retrograde impedance changes/bolus movements ("pH-MII method") 2. Creating non-mealtime pH measurements anytime the pH fell below 4 regardless of impedance changes ("all-pH method"). Statistical analysis was performed using ttest, Fischer's test, and logistic regression. Results: 121 patients were eligible. The mean percent total acid exposure time (4.05) was significantly higher in the all-pH method (vs. 1.63, p=0.001). The proportion of patients with abnormal acid exposure time (24.7%) and DeMeester score (24.8%) was higher in the all-pH method (vs. 8.3%, p=0.001; vs. 9.1%, p=0.002). Compared to those without a hiatal hernia (HH), more patients with a HH >2cm had significant differences between analysis methods in upright (19.4% vs. 5.56%, p=0.03), recumbent (29% vs. 6.67%; p=0.002), total time (45.2% vs. 6.67%, p=0.001), and DeMeester score (35.5% vs. 8.89%; p=0.001). Adjusting for age, sex, and PPI usage, HH remained a significant predictor of whether results would differ (OR 12; CI 3.34-42.8 total exposure, OR 8.75; CI 2.36-32.5 DeMeester). Conclusion: Analysis of esophageal acid exposure using all pH data detected more acid reflux than when incorporating impedance measures, particularly in those with a HH. This finding may Medical Research Archives Volume 4 Issue 4.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations鈥揷itations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.