Obesity is associated with increased 48-h esophageal acid exposure in patients with symptomatic gastroesophageal reflux.
OBJECTIVE
Obesity has been associated with gastroesophageal reflux disease (GERD) but the relationship between body mass index (BMI) and esophageal acid exposure remains poorly understood. We hypothesized that overweight (OW) and obese (OB) patients with GER symptoms would have a higher degree of esophageal acid exposure than with normal weight (NW) patients.


METHODS
157 patients separated in groups according to BMI were studied for 48h while off antisecretory medications using ambulatory wireless capsule pH-metry. The pH capsule was appropriately positioned and esophageal pH data were collected. Appropriate univariate and multivariate statistical methods were used.


RESULTS
Groups did not differ in age, but more women were in the NW group. OB patients had a fivefold increase in odds for abnormal total acid exposure compared with NW (OR=5.01; 95% CI 2.94, 12.95). Total acid exposure time (AET) was elevated in OB (8.7%+/-5.1%) compared with NW (5.3%+/-5.2%; P<0.05). AET was highest during awake, upright periods. The DeMeester score was higher in OB (31.7+/-19.2) and OW (26.0+/-16.8) groups compared with the NW (19.8+/-17.6) group (P<0.001). AET increased from day 1 to day 2 in the OB group only.


CONCLUSIONS
This is the first study to report a positive relationship between BMI and esophageal acid exposure time using prolonged, continuous wireless esophageal pH-metry. Abnormal AET was more frequent in OB patients. Variability in AET increased from day 1 to day 2 in the OB group, supporting the use of more prolonged pH studies in subsets of patients.
Crowell
Michael D
MD
Division of Gastroenterology and Hepatology, Mayo Clinic, Scottsdale, Arizona, USA. crowell.michael@mayo.edu
Bradley
Angela
A
Hansel
Stephanie
S
Dionisio
Paula
P
Kim
Hack Jae
HJ
Decker
G Anton
GA
DiBaise
John K
JK
Sharma
V K
VK
D016145:Endoscopy, Digestive System; D049630:Esophageal Sphincter, Lower / Q000503:physiopathology; D050782:Esophageal pH Monitoring; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*