Acid Reflux Detection and Symptom-Reflux Association Using 4-Day Wireless pH Recording Combining 48-Hour Periods Off and On PPI Therapy

Abstract

Studies have shown that extended pH recording improves the sensitivity of esophageal pH monitoring. Controversy exists as to whether pH studies are optimally done off or on proton pump inhibitor (PPI) therapy. The aim of this study was to incorporate periods both off and on PPI therapy in a single, extended pH test and describe the effect of PPI therapy on symptom-reflux associations. Sixty patients underwent 4-day pH recordings using two separate receivers calibrated to a single wireless pH capsule. Patients were off PPI therapy for days 1 and 2. Either rabeprazole 20 mg twice daily or omeprazole/sodium bicarbonate 40 mg twice daily were administered on days 3 and 4. Symptom-reflux correlation was determined by the symptom index (SI), symptom sensitivity index (SSI), and symptom association probability (SAP). Twenty studies were excluded due to premature detachment (9) or incomplete data capture for >6 of the 96-h period (11). Off therapy, 14 patients (35%) had abnormal esophageal acid exposure values. On day 4, 39 patients (98%) had normal acid exposure. The number of symptoms and acid reflux events were significantly higher off PPI therapy. Furthermore, the percentage of patients with a positive SI fell from 50% off PPI to 9% on PPI (P < 0.01), whereas 63% of patients symptomatic off PPI therapy became asymptomatic on PPI therapy and could not have an SI calculated. Similarly, the SAP was abnormal in 45% of patients off PPI therapy but only 10% on PPI therapy (P < 0.01). Extended pH recording improves the detection of abnormal acid reflux and increases the number of recorded symptoms and acid reflux events. Combined off and on PPI therapy pH testing enhances the interpretation of pH monitoring and symptom-reflux correlations, which can be helpful in the management of patients with PPI-unresponsive gastroesophageal acid reflux symptoms.