[Characteristics of different phenotypes of refractory non-erosive gastroesophageal reflux disease]

Objective: To investigate the characteristics of different phenotypes of refractory non-erosive gastroesophageal reflux disease (NERD), the types of esophageal motility and the related factors of symptoms. Methods: A retrospective analysis was made of the patients with refractory NERD of Beijing Tongren Hospital affiliated to Capital Medical University from September 2015 to August 2017. All patients underwent electronic gastroscopy, esophageal manometry and 24-hour dynamic esophageal pH impedance monitoring. They were divided into four phenotype groups according to the results. Results: A total of 231 patients were enrolled in the study. There were 111(48.1%)cases in phenotype 1 group, 9 (3.9%)cases in phenotype 2 group, 100 (43.3%)cases in phenotype 3 group and 11 (4.8%) cases in phenotype 4 group. Compared with the other three groups, the number of weak acid reflux [(86±55) vs (37±8), (70±52), (31±9) times] and the number of gas reflux [(86±76) vs (38±13), (58±57), (26±10)] in phenotype 1 group increased significantly (allP<0.005). Dynamics disorders were common in refractory NERD patients (139/231, 60.2%). Mild esophageal dynamics disorder was the main type of dynamics disorder (118/139, 84.9%). There was no significant difference among the phenotype groups. Multivariate unconditional Logistic regression analysis showed that the risk factors for reflux-related symptoms were female ratio, Chicago power classification, gas reflux and weak acid reflux (OR=3.731, 2.452, 1.036 and 1.037, P<0.05). Conclusions: The characteristics of gastroesophageal reflux and the types of motility disorders are different in different phenotype groups of refractory NERD patients. The risk factors of reflux-related symptoms are female ratio, Chicago motility classification, gas reflux and the frequency of weak acid reflux.