African–Americans, Hispanic Americans, and Non-Hispanic Whites Without GERD or Reflux Symptoms Have Equivalent 24-h pH Esophageal Acid Exposure

Abstract

Ambulatory esophageal pH monitoring is, currently, the recommended diagnostic exam for gastroesophageal reflux disease. Data are currently available for African-American (AA) and non-Hispanic white (nHw) volunteers among United States ethnic groups. The purpose of this study was to obtain normal values of 24-h esophageal pH by monitoring healthy adult Hispanic American (HA) volunteers and to compare these with values obtained from healthy AA and nHw volunteers to determine if ethnic variation exists in 24-h esophageal pH. 24-h Dual esophageal pH monitoring was performed for healthy AA, HA, and nHw. Values for total number of reflux episodes, episodes longer than 5 min, total reflux time, and longest reflux episode in the proximal and/or distal esophagus were obtained for all groups. Differences between groups were considered significant if p<0.05. One-hundred and thirty-six subjects volunteered and completed 24-h pH testing. Fifty-three were AA, 25 HA, and 58 nHw, with males accounting for 52, 47, and 47%, respectively, of each group. AA were older than nHw only and nHw had a lower body mass index than both AA and HA. Shorter study duration was observed for HA than for AA and nHw. No difference was observed between ethnic groups for any measured pH data in the proximal or distal esophagus. No difference exists in values obtained during esophageal pH monitoring among healthy AA, HA, and nHw. This indicates that currently accepted normal values of ambulatory esophageal pH monitoring can be used for all major United States ethnic groups without compromising diagnostic accuracy.