Correlation between pathological distal esophageal acid exposure and ineffective esophageal motility

To assess the correlation between esophageal dysmotility, characterized as inefficient esophageal motility (IEM), and the presence of pathological acid reflux due to a structurally defective lower esophageal sphincter (LES), hiatus hernia. (HH), or esophagitis in patients with suspected gastroesophageal reflux disease (GERD).

311 patients referred for GERD diagnostic procedures in a gastroesopahgeal motility laboratory were included in the study. Patients underwent an interview regarding their clinical symptoms, upper endoscopy (UE), stationary esophageal manometry, and 24-h esophageal pH-metry. The following risk factors of patients in the negative pH-metry group were compared to those in the positive pH-metry group: IEM, defective LES, HH, and esophagitis. The association between IEM and positive pH-metry results was first assessed by means of univariate analysis and later determined with multivariate logistic regression analysis.

Out of the total of 311 studied patients, 208 met the inclusion criteria; 88 had normal and 120 had positive pH-metry results. Univariate analysis revealed that the occurrence of IEM, defective LES, and HH was significantly greater in the positive pH-metry group. Following logistic regression analysis, the occurrence of IEM remained significantly greater in the positive pH-metry group.

IEM is associated with the presence of abnormal acid reflux, as assessed by 24-h esophageal pH-metry, regardless of the presence of defective LES, HH, or esophagitis.