Normal ambulatory 24-hour esophageal pH values in Koreans -a multicenter study-

Area of Science:

• Gastroenterology
• Digestive Physiology

Background:

• Ambulatory 24-hour esophageal pH monitoring is the gold standard for diagnosing gastroesophageal reflux disease (GERD).
• Establishing population-specific normal values is essential for accurate diagnosis.

Purpose of the Study:

• To determine the normal range of gastroesophageal acid exposure in healthy Korean adults.
• To provide reference data for GERD diagnosis in the Korean population.

Main Methods:

• Fifty healthy Korean volunteers (24 males, 26 females; mean age 45) underwent ambulatory 24-hour esophageal pH monitoring.
• Participants had no reflux symptoms, esophagitis, or hiatal hernia confirmed by upper endoscopy and esophageal manometry.

Main Results:

• The 95th percentile values for key reflux parameters were established, including percent total time pH <4 (3.7%), percent upright time pH <4 (5.7%), and percent supine time pH <4 (1.0%).
• Other parameters included the number of reflux episodes (76.5), prolonged reflux episodes (1.5), longest episode duration (12.5 min), and a composite score (14.2).
• No significant association was found between age, gender, and measured pH parameters.

Conclusions:

• Physiological gastroesophageal reflux is present in healthy Korean individuals.
• The established normal esophageal pH values serve as essential reference data for clinical and research applications in Korea.