Excessive supragastric belching can be identified in up to one-fifth of patients with conclusive gastro-oesophageal reflux disease

Background Supragastric belching (SGB) can trigger reflux episodes, but the contribution of SGB to pathological reflux burden is incompletely understood. Objective To characterise and identify clinical predictors for excessive SGB-related gastro-oesophageal reflux disease (GERD) phenotype. Design This was a multicentre cross-sectional study of patients with acid exposure time (AET) >6% on pH-impedance monitoring off therapy across 11 international tertiary centres. SGB episodes were manually identified. Excessive SGB was defined by ≥13 episodes/24 hours. SGB-related AET was determined by duration of pH <4 following an SGB episode. Univariate and multivariable analyses assessed relationships between excessive SGB and conclusive GERD. Results Of 580 patients (age 56.1±0.6 year, 62% women) from four world regions (Europe/North America/Latin America/Asia), 107 (18.5%) had excessive SGB (p=0.97 across regions). Excessive SGB-related GERD phenotype had lower total AET (p=0.01) with 24.6±2.2% total AET attributable to SGB, higher total reflux episodes (TRE, p=0.0006) and higher number of SGB-related symptom episodes (p<0.0001). On logistic regression, higher TRE (OR 1.01, 95% CI 1.004 to 1.014, p=0.0004) independently predicted excessive SGB, while predominant perceptive symptoms (heartburn/chest pain, OR 0.36, 95% CI 0.155 to 0.854, p=0.002) and higher distal AET (OR 0.96, 95% CI 0.920 to 0.998, p=0.042) were negative predictors. On receiver-operating characteristics curve analysis, >115 TRE and >56 proximal reflux episodes achieved >90% specificity for excessive SGB. Conclusions Excessive SGB is found in up to 20% of patients with conclusive GERD, with 25% of AET attributable to SGB. Higher TRE (>115 TRE, >56 proximal episodes) and more SGB-associated symptoms are predictors of excessive SGB-related GERD phenotype.