Introduction Oesophageal pH-impedance monitoring is the gold standard for the diagnosis of gastroesophageal reflux disease (GORD). The DeMeester score is a global measure of acid exposure calculated from reflux parameters. Symptom Index (SI) and the Symptoms Association Probability (SAP) scores correlate symptoms to episodes of gastroesophageal reflux (GOR). Currently, it is not clear which of these scoring methods best relate to the patient’s response to treatment. This study investigates the value of these 3 metrics in predicting the clinical outcome of treatment in GORD patients.
Methods We retrospectively selected patients who had 24 hour pH-impedance monitoring on suspicion of GORD during December 2014 to October 2015. Abnormal DeMeester was defined as ≥14.72, +ve SI as ≥50%, and +ve SAP as ≥95%. The Reflux Disease Questionnaire (RDQ) was completed by each patient before investigation. After reflux monitoring, patients were followed up to calculate their post-treatment RDQ at least 2 months post treatment. Sensitivity, specificity, positive and negative likelihood ratios and predictive values were calculated.
Results 42 patients (11 male; total mean age 51 [25–79]) were included. 25 (59.52%) of these patients were treated. Of these, 21 patients, had medical treatment and 6 had surgical treatment (2 had both). 10/25 (40%) had a reduced RDQ score post-treatment: 8/10 (80%) having medical treatment, 1/6 (23.33%) having surgical treatment. In patients without treatment, 7/17 (41.18%) had a reduced RDQ. The two-tailed p value between the treated and untreated group was not significant (p = 1.00).
Considering individual metrics, abnormal DeMeester score showed highest specificity and SAP showed the highest sensitivity in predicting lowering RDQ score post-treatment. When combining different metrics, having all three parameters positive yielded the highest overall clinical value: sensitivity 60%, specificity 95%, positive likelihood ratio 12, positive predictive value 75%, negative predictive value 90% (table 1).
Conclusion In patients diagnosed with GORD by pH-impedance monitoring, having all three parameters positive i.e. abnormal DeMeester score, SAP +ve and SI +ve had a high overall value in predicting the response to treatment. Nevertheless, reduction of RDQ was equally seen in untreated GORD group. A study on a larger number of patients might be required to further confirm the findings of this research
Disclosure of Interest None Declared