Published online Mar 25, 1996. doi: 10.3748/wjg.v2.i1.9
Revised: August 31, 1995
Accepted: December 1, 1995
Published online: March 25, 1996
AIM: To establish the optimal thresholds of pH variation (pH fluctuations and reflux episodes) for separating physiological and pathological gastroesophageal reflux (GER), and to evaluate their significance for GER diagnosis.
METHODS: Twenty-four hour intraesophageal pH monitoring and endoscopy were performed in 400 patients with GER symptoms and in 100 healthy controls.
RESULTS: The percentages of the time with pH fluctuations in patients with and without esophagitis, and in healthy controls were, on average, 12.65%, 9.5% and 2.76% in 24 h, respectively, and the respective percentages of the time with reflux episodes in the same groups in 24 h were, on average, 3.12%, 2.04% and 0.18%, respectively. Using a receiver-operating-characteristic curve analysis, < 6.7% of the time with pH fluctuations and 0.1% of the time with reflux episodes were defined as the combined thresholds for physiological versus pathological reflux. The sensitivity of the combined thresholds for the detection of GER in patients with and without esophagitis was 96.7% and 90.0%, respectively, and the specificity for the diagnosis of patients with abnormal GER disease was 100%.
CONCLUSION: pH fluctuations and reflux episodes, when evaluated together, are more useful for classifying patients with GER; the combined thresholds yield higher diagnostic accuracy for assessing patients with GER disease.