{
  "abstract": "Introduction EndoFLIP (FLIP) enables real time assessment of gastro-oesophageal junction (GOJ) and oesophageal contractility during gastroscopy (OGD), but its diagnostic value in gastro-oesophageal reflux disease (GORD) is uncertain. We evaluated whether FLIP metrics are influenced by age, sex, and sedation, and whether they discriminate GORD defined by prolonged ambulatory pH monitoring (Bravo).Methods Adults with reflux symptoms underwent OGD, FLIP and Bravo in a single session as part of a prospective research study (IRAS 304275). GORD was classified as per Lyon 2.0 alongside validated symptom scores. FLIP metrics included GOJ distensibility index (DI), diameter, pressure, opening behaviour and Dallas consensus oesophageal motility patterns, including rate of repetitive antegrade contractions (RACs). Associations with reflux metrics were analysed using non-parametric tests, linear regression and receiver-operator characteristic (ROC) analysis.Results 108 patients were included; mean age 46.9 years, 61% female. By Lyon 2.0, 47 had GORD, 31 did not have GORD and 26 were inconclusive.FLIP metrics did not differ between GORD and non-GORD groups, including DI, GOJ diameter, pressure, oesophageal motility pattern and rate of RACs (all p>0.05). FLIP did not discriminate abnormal from normal acid exposure time (AET), with poor diagnostic performance (minimum DI at 60 ml: AUC 0.53; figure 1). Minimum DI at 60 ml demonstrated a modest positive linear association with total, worst-day and nocturnal AET (R2 0.05–0.10; p<0.05); however, rank correlations were not significant (Spearman r=0.01–0.09, p>0.3), and discrimination remained poor on ROC analysis.In contrast, increasing age was associated with lower DI (Spearman r=–0.49, p<0.0001), smaller GOJ diameter, reduced likelihood of GOJ opening and reduced contractile activity (all p<0.001). Female patients had lower DI than males (median 3.30 vs 4.35 mm2/mmHg, p=0.003), independent of reflux status.There was no correlation between midazolam or fentanyl dose and DI (all p>0.25). FLIP motility patterns were normal for 75% and did not differ by GORD status. RAC rate declined with increasing age (Spearman r=–0.39, p<0.0001) but was not associated with reflux metrics. Propofol sedation was associated with a higher prevalence of abnormal motility patterns and reduced RAC frequency; however, this finding was limited by small numbers.ROC curve demonstrating poor discrimination of abnormal total acid exposure time (>6%) by GOJ distensibility index at 60 ml (AUC 0.53, 95% CI 0.42–0.64).Conclusions FLIP demonstrates age and sex related GOJ and oesophageal body physiological effects independent of reflux burden and sedation. However, these measures do not discriminate GORD, challenging the assumption that reduced GOJ tone or altered oesophageal motor activity alone predispose to GORD and highlight the complex nature of GORD ­pathogenesis.Abstract P149 Figure 1ROC curve, minimum DI (60ml) vs total AET >6%",
  "authors": [
    {
      "affiliations": [
        "St George’s University Hospitals NHS Foundation Trust, London, United Kingdom",
        "City St George’s, University of London, London, United Kingdom"
      ],
      "name": "Joseph Cooney"
    },
    {
      "affiliations": [
        "St George’s University Hospitals NHS Foundation Trust, London, United Kingdom"
      ],
      "name": "Priscilla Appiahene"
    },
    {
      "affiliations": [
        "St George’s University Hospitals NHS Foundation Trust, London, United Kingdom"
      ],
      "name": "Anna Wolak"
    },
    {
      "affiliations": [
        "St George’s University Hospitals NHS Foundation Trust, London, United Kingdom"
      ],
      "name": "Alice Henderson"
    },
    {
      "affiliations": [
        "St George’s University Hospitals NHS Foundation Trust, London, United Kingdom",
        "City St George’s, University of London, London, United Kingdom"
      ],
      "name": "Jamal Hayat"
    }
  ],
  "title": "P149 EndoFLIP derived oesophageal physiology varies with age and sex but not sedation or reflux disease",
  "uid": "44c6dbcb-28f9-51b2-8b6a-e9ce4c1da49b"
}