The role of shorter than 24-h pH monitoring periods in the diagnosis of gastro-oesophageal reflux.

We studied 20 patients with typical symptoms of gastro-oesophageal reflux, to determine whether the diagnostic accuracy of 24-h pH monitoring might be retained in a test using a shorter time. The duration and number of reflux episodes were used to calculate a frequency and duration score (FDS) for the 24-h period, the daytime period, the nighttime period, a 3-h postprandial period after eating a test meal (provocation test), and a 21-h period that excluded this 3-h postprandial period. The daytime FDS was significantly higher than nighttime FDS (p less than 0.02), and there was good correlation between the 21-h FDS and the 3-h postprandial FDS (rs = 0.695; p less than 0.01). We conclude that the 3-h postprandial testing after a standard meal provocation test is a practical, accurate, and well-tolerated method of diagnosing gastro-oesophageal reflux. The results also demonstrated the relative importance of daytime as opposed to nocturnal reflux in producing symptoms and oesophagitis.