Impact of bile acids on the severity of laryngo-pharyngeal reflux

Objectives: The primary end point of this study was to evaluate the impact of bile acids on severity of laryngo-pharyngeal reflux (LPR) and the possible correlation with esophagitis and upper airway malignancies. The second end point was to evaluate if salivary bile acids and molecules other than pepsin might serve as diagnostic biomarkers of LPR. Design: Observational prospective comparative study. Setting: Otorhinolaryngology unit of a tertiary hospital. Participants: Sixty-two consecutive adult outpatients suspected of LPR. Main outcome measures: Bile acids, bilirubin and pepsinogen I-II were measured in saliva. Patients underwent pH metry and based on the results of bile acids were subdivided as acid, mixed and alkaline LPR. Results: Significantly higher Reflux Findings Score (RFS) and Reflux Symptoms Index (RSI) were seen in patients with alkaline and mixed LPR compared to acid LPR. Salivary bile acids >1 µmol/L seem to be a reliable indicator of the severity of LPR. Compared to those without, patients with esophagitis or a history of upper airway malignancy have high concentrations of bile acids in saliva. Among the molecules studied, bile acids were the most suitable for diagnosis of LPR, with a sensitivity of 86% and a positive predictive value of 80.7%. Conclusions: Our data suggest that high concentrations of bile acids are associated with higher values of RSI and RFS in LPR as well as a higher risk of esophagitis and history of upper airway malignancies. We finally observed that bile acids provided the best biometric parameters for diagnosis of LPR among the molecules tested.