Introduction: An association between obesity and GERD symptoms has been reported; however, study results have been inconsistent and it is not known whether an association persists after adjusting for other known GERD risk factors.
Methods: We carried out a cross-sectional study to determine the prevalence and risk factors of GERD in volunteers (VA employees). Participants completed a Gastroesophageal Reflux Questionnaire, the Block 98 Food Frequency Questionnaire, provided height and weight information, and were invited for upper endoscopy with biopsies. Associations of body mass index (BMI) with GERD symptoms and erosive esophagitis were examined separately in multiple logistic regression analyses adjusting for age, sex, race, GERD symptoms, dietary intake, education level, family history of GERD, H. pylori infection, and the presence and distribution of gastritis.
Results: Four hundred and fifty-three persons (mean age 44 yr, 70% women and 43% black) provided complete information on heartburn, regurgitation, and BMI (50% of 915 who received questionnaires). Of the 196 who underwent endoscopy, 44 (22%) had esophageal erosions and 118 (26%) reported at least weekly heartburn or regurgitation. A dose-response relationship between frequency of heartburn or regurgitation and higher BMI was observed. Compared to participants without weekly symptoms, a significantly larger proportion of the 118 with these symptoms were either overweight (BMI 25-30) (35% vs 32%) or obese (BMI>30) (39% vs 26%), p for linear trend 0.004. Relative to those with no esophageal erosions, those with erosions were more likely to be overweight (39%vs 26%) or obese (41% vs 32%), p=0.04. Obese participants were 2.5 times as likely as those with normal BMI (<25) to have reflux symptoms or esophageal erosions. The association between BMI and GERD symptoms persisted in direction and magnitude after adjustment for potential confounders.
Conclusions: Overweight and obesity are strong independent risk factor of GERD symptoms and esophageal erosions. The amount or composition of dietary intake does not appear to be a likely explanation for these findings.