Frequency of abnormal esophageal acid exposure in patients eligible for bariatric surgery

Obesity and gastroesophageal reflux disease (GERD) are both high-prevalence diseases in developed nations. Obesity has been identified as an important risk factor in the development of GERD. The objective of this study was to determine the frequency of abnormal esophageal acid exposure in patients candidate for bariatric surgery and its relationship with any clinical and endoscopic findings before surgery.

Data collected from a group of 88 patients awaiting bariatric surgery included a series of demographic variables and symptoms typical of GERD. The tests patients underwent included manometry, pH monitoring, and upper gastrointestinal endoscopy. Univariate and multivariate analyses were conducted on the variables related to the onset of reflux.

Esophageal pH monitoring tests were positive in 65% of the patients. Manometries showed lower esophageal sphincter hypotonia in 46%, while 20% returned abnormal upper endoscopy results. Out of the 45% of patients who were asymptomatic or returned normal endoscopies, half returned positive esophageal pH tests. In turn, among the 55% of patients who had symptoms or an abnormal upper endoscopy, three quarters had pH tests that diagnosed reflux. pH tests were also positive in 80% of symptomatic patients and 100% of patients with esophagitis (P<.042). No statistically significant relationship was found between body mass index, sex, age, manometry, or hiatus hernia and the positive pH monitoring.

Frequency of abnormal esophageal acid exposure among obese patients is high. There is a relationship between the presence of symptoms and reflux. But the absence of symptoms does not rule out the presence of abnormal esophageal function tests.