Distal esophageal acid exposure can be quantified using the DeMeester score (DS) or percentage time pH<4. In addition to these parameters, symptom index (SI) is used to evaluate the association of symptoms and acid reflux. Combined analysis (CA) including the SI and percentage time pH<4 provides a more comprehensive interpretation of pH monitoring results.Aim
To assess whether using CA compared with DS is more accurate for interpretation of pH monitoring.Method
pH studies from 450 patients (303 female; mean age 53; range 11 to 88) off therapy between July 2002 and October 2004 were analyzed. DS (normal<14.7), percentage time pH<4 (normal; upright<6.3%, recumbent<1.2%), and the SI (positive symptom if ≥50%) were calculated for each patient. Symptom responses to proton pump inhibitors (PPIs) were assessed in patients with discordant DS and CA.Results
Sixty-six patients were identified as having a normal DS and an abnormal CA. Forty-one (62%) patients had abnormal reflux according to the CA and 25 (38%) had normal reflux but a positive SI. Ten patients were lost to follow-up, 43 (84%) improved on and were currently taking a PPI and 8 (16%) found no benefit from taking a PPI. Five (9%) patients were never tried on a PPI and 3 were still symptomatic. Twenty-two (88%) patients with a positive SI and normal reflux were followed-up (3 never prescribed PPI) and 17 (90%) improved with a PPI.Conclusions
Interpreting the results of pH monitoring based solely on the composition DS misses patients with an acid “sensitive esophagus,” a group of patients who benefit from PPI therapy.