Objective: Evaluate the associations between abdominal obesity and gastroesophageal reflux disease (GERD), and their interactions with ethnicity and gender.
Design: A cross-sectional study. Participants completed detailed symptom questionnaires and underwent a standardized examination, including anthropometric measurements.
Setting: A large integrated care health system.
Patients: 80,110 members of the Kaiser Permanente multiphasic health check-up cohort.
Main Outcome Measures: Gastroesophageal reflux-type symptoms.
Results: Recent reflux-type symptoms were present in 11% of the population. The multivariate odds ratio for symptoms with an abdominal diameter (adjusted for BMI) of ≥26 vs. <16.3 centimeters was 1.85 (95% confidence interval [CI] 1.55-2.21) for whites, 0.95 (95% CI 0.61-1.48) for blacks, and 0.64 (95% CI 0.18 - C 2.30) for Asians. The mean abdominal diameter was greater in men (22.0 centimeters, 95% CI 21.9-22.0) than in women (20.1 centimeters, 95% CI 20.0-C20.1; p<0.01), but the risk of symptoms for any given diameter did not differ markedly by gender. The association between increasing BMI and symptoms was also much stronger among whites than among blacks. The association between BMI and reflux-type symptoms was partially mediated through abdominal diameter.
Conclusions: There was a consistent association between abdominal diameter (independent of BMI) and reflux-type symptoms in whites, but there were no consistent associations in blacks or Asians. The association was also strongest among whites. These findings, combined with the increased prevalence of abdominal obesity in males, suggest that increased obesity may disproportionately increase GERD-type symptoms in whites and in males.