PT  - JOURNAL ARTICLE
AU  - Frazzoni, Leonardo
AU  - Frazzoni, Marzio
AU  - De Bortoli, Nicola
AU  - Ribolsi, Mentore
AU  - Tolone, Salvatore
AU  - Russo, Salvatore
AU  - Conigliaro, Rita Luisa
AU  - Penagini, Roberto
AU  - Fuccio, Lorenzo
AU  - Zagari, Rocco Maurizio
AU  - Savarino, Edoardo
TI  - Application of Lyon Consensus criteria for GORD diagnosis: evaluation of conventional and new impedance-pH parameters
AID  - 10.1136/gutjnl-2021-325531
DP  - 2022 Jun 01
TA  - Gut
PG  - 1062--1067
VI  - 71
IP  - 6
4099  - http://gut.bmj.com/content/71/6/1062.short
4100  - http://gut.bmj.com/content/71/6/1062.full
SO  - Gut2022 Jun 01; 71
AB  - Objective To validate Lyon Consensus criteria for diagnosing gastro-oesophageal reflux disease (GORD) by reflux monitoring.Design Manual review of impedance-pH tracings from patients with proton pump inhibitor (PPI)-dependent heartburn, evaluated off PPI. Acid exposure time (AET) thresholds defined by the Lyon Consensus and impedance parameters were investigated, namely, total refluxes (TRs), postreflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI).Results The study included 488 patients, 178 (36%) with normal (<4%) AET, 89 (18%) with inconclusive (4%–6%) AET and 221 (45%) with abnormal (>6%) AET, alongside with 70 healthy controls. At receiver operating characteristic analysis, area under curve was 0.89, 0.95 and 0.89 for TRs, PSPW index and MNBI, respectively, and threshold values were 40, 50% and 2000 Ω; the 4% physiological AET threshold defined by the Lyon Consensus showed 100% specificity but 63% sensitivity. The thresholds defined for impedance parameters were validated against AET by means of ordered logistic regression, being in concordance with the 4% AET threshold (OR 2.5 for TRs, 18.9 for PSPW index and 5.7 for MNBI). TRs positivity and concordant PSPW index/MNBI positivity were found in 80%–90% of patients in the abnormal AET group, in 73%–74% of cases in the inconclusive AET group and in 28%–40% of cases in the group with normal AET.Conclusions Our results show the overall validity of the Lyon Consensus approach to GORD diagnosis. Adding evaluation of impedance parameters, namely, TRs, PSPW index and MNBI to AET appraisal, substantially improves the diagnostic yield of reflux monitoring.Data supporting the study are available on reasonable request from the corresponding author.