Tu1772 Comparison of Proximal and Distal Impedance Episodes in Patients With Classic Versus Extra-Esophageal Symptoms of GERD

Background: Patients are frequently referred for evaluation of extraesophageal (EXT) symptoms (cough, hoarseness, globus sensation) presumably related to gastroesophageal reflux disease (GERD). 24 hour pH/impedance is the most sensitive test for the diagnosis of GERD, however limited data exist in examining the relationship between distal and proximal impedance episodes in patients with EXT symptoms versus classic reflux symptoms. Aim: To compare the number and percentage of proximal impedance episodes in patients with EXT symptoms to those with classic GERD symptoms undergoing 24 hour pH/impedance testing. Patients & Methods: A retrospective review of adult patients undergoing esophageal manometry and 24 hour pH/impedance studies off acid suppressing therapy between 20062011 was performed. Indications for these studies included typical GERD symptoms (heartburn and regurgitation) or atypical symptoms (cough, asthma, hoarseness or globus sensation). GERD was defined using the validated Johnson-DeMeester (JD) score. The results of the esophageal manometry and 24 hour pH/impedance studies between the classic GERD and EXT groups were compared using Chi squared test and students independent t-test. Continuous data is expressed as means (sd). Results: A total of 220 patients were included in the analysis [172 GERD vs. 48 EXT]. GERD and EXT groups were similar in race and gender, however GERD patients were younger than EXT patients [46 (13) years vs. 50 (8) years, p = 0.048]. There was no significant difference between GERD and EXT in the mean number of proximal impedance episodes [33 (22) vs. 28 (22), p = 0.188], the percentage of proximal impedance episodes migrating from the distal esophagus [55 (20) % vs. 50 (17) %, p=0.178), or the mean number of distal impedance episodes [57 (33) vs. 49 (34), p = 0.157]. There was no significant difference between GERD and EXT with regards to mean lower esophageal sphincter pressures [13.3 (11) mmHg vs. 15.3 (7.8) mmHg, p = 0.251] or mean esophageal amplitude [95.4 (44.6) mmHg vs. 84.9 (41.0) mmHg, p=0.146]. Based on 24 hour pH monitoring there was no significant difference between the classic GERD and EXT groups in the JD scores [22.6 (33) vs 17.8 (22), p = 0.358] or percent total time pH ,4 [4.6 (5.3) vs. 4.2 (5.3), p = 0.642]. There was a significant correlation between the number of proximal and distal episodes between the two groups (R = 0.724, p , 0.001). Conclusion: Patients with EXT symptoms are similar to classic GERD patients in the number proximal impedance reflux episodes and percentage of distal episodes migrating to the proximal esophagus. Furthermore, both groups have a similar degree of acid reflux.