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.