A prospective study has demonstrated for the first time that there is a direct relationship between gastric acid suppression and healing of erosive esophagitis due to acid reflux disease, according to a presentation at the annual Digestive Disease Week.

The trial was a double-blind, prospective study to assess the relationship between the amount of time intragastric pH was greater than 4 and healing of endoscopically verified severe erosive esophagitis (grade C or D according to the Los Angeles Classification System).

Patients were randomized to esomeprazole 10 mg or 40 mg daily for four weeks. The study was not designed to compare the doses but rather to investigate a broad range of acid control.

Patients underwent an intra-esophageal/intra-gastric 24-hour pH study on day five. At week four, an endoscopist blinded to the pH study evaluated whether or not each patient's erosive esophagitis had healed. In addition, acid reflux disease symptoms were scored before treatment and at four weeks, prior to the final endoscopy.

Analyses included 103 patients who completed the pH study and final endoscopy and met predetermined protocol criteria. Of this group, 72 patients had healed erosive esophagitis at four weeks.

Researchers found that patients were more likely to have healing of erosive esophagitis if gastric acid was well controlled after five days of therapy. Gastric acid control was defined as intragastric pH greater than 4. Among patients whose esophagitis healed, 61.3 percent had good acid control at day five. In contrast, only 42.1 percent of patients whose esophagitis had not healed had good acid control at day five.

A post hoc analysis showed that healed patients also experienced a longer duration of acid control in the esophagus (95.2 percent of a 24-hour period) compared with unhealed patients (88.9 percent of a 24-hour period), a statistically significant difference.

Better acid control also correlated to significantly lower heartburn and acid regurgitation symptom scores.

"This is the first prospective study that showed an association between control of intragastric pH and clinical outcomes in GERD patients," said Philip Katz, MD, lead author of the study. "The results further support intragastric pH as a surrogate marker for assessing the efficacy of antisecretory therapy in GERD."