P2381 - Variations in Esophageal Nocturnal Impedance Values Throughout the Sleep Period in Gastroesophageal Reflux Disease Patients

Tuesday, October 26, 2021

10:30 AM – 4:00 PM PT

Location: Shoreline Exhibit Hall

Has Audio

Presenting Author(s)

Ali El Mokahal, MD

MetroHealth Medical Center
Cleveland, OH, United States

Ali El Mokahal, MD¹, Fahmi Shibli, MD¹, Serge Baroud, MD¹, Gengqing Song, MD¹, Ronnie Fass, MD²
¹MetroHealth Medical Center, Cleveland, OH; ²Esophageal and Swallowing Center, MetroHealth Medical Center, Case Western Reserve University, Cleveland, OH

Introduction: 24-hour esophageal pH/Impedance monitoring provides assessment of gastro-esophageal reflux (GER). Impedance monitoring assess mucosal integrity or damage. The mean nocturnal baseline impedance (MNBI), calculated as a mean of 3 measurements of nocturnal impedance at 1, 2 and 3 am, has been found to be a reliable tool to identify GERD. However, thus far variations of esophageal impedance during sleep time have not been described. The aim of this study was to determine the variations of esophageal nocturnal impedance during sleep time in patients with GERD on once or twice daily PPI.

Methods: A total of 242 GERD patients who completed 24- hour esophageal pH and impedance monitoring were included in this study. All patients were receiving once (OD) or twice (BID) daily PPI. Sleep time of each patient was divided into four quartiles (first, second, third and fourth). Nocturnal impedance was calculated at the beginning of each of the four quartiles, avoiding swallows and reflux episodes. MNBI was also calculated for each patient. Comparison of nocturnal impedance variations between patients receiving PPI once daily versus those on twice daily were also carried out. Analysis of variance (ANOVA) was used to compare the mean of patients on OD and BID PPI dosing.

Results: Of those recruited, 79 (32.6%) patients were on OD dosing and 163 (67.4%) patients on BID dosing. Mean age was 53 years and 75% were females. The mean nocturnal impedance values at 1, 2 and 3 am for once daily were, 2160 ± 160, 1996 ± 146 and 2369 ± 184, respectively, and for twice daily 2305 ± 11, 2381 ± 115, 2487 ± 118, respectively. Impedance values also increased across the 4 quartiles, from 2603 ± 189 in the first quartile to 2850 ± 178 at the fourth quartile in the OD PPI group and from 2603 ± 189 in the first quartile to 2850 ± 178 at the fourth quartile in the BID PPI group. (Table 1, Figure 1b). Overall, nocturnal impedance increases with time as sleep progresses. There was no statistically significant difference calculated in the MNBI of patients on OD compared to BID PPI (2175 ± 1223) vs. (2394 ± 1287) P =0.211.

Discussion: Esophageal nocturnal impedance increases as sleep time progresses, suggesting variations in values that are dependent on sleep time. These is no difference in impedance between OD and BID PPI. Our study suggests reevaluating the current arbitrary practice of measuring MNBI at 1, 2, 3 AM.

Figure: Fig 1a. Impedance across four quartiles of supine time (OD and BID Dosing) Fig 1b. Impedance across for quartiles of supine time (OD and BID Dosing)

N = 242	Mean ± SE	Patients on once daily PPI (N = 79)	Patients on twice daily PPI (N = 163)	P value
Basal Impedance at 1AM	2258 ± 91	2160 ± 160	2305 ± 111	0.456
Basal Impedance at 2 AM	2255 ± 92	1996 ± 146	2381 ± 115	0.048
Basal Impedance at 3 AM	2449 ± 100	2369 ± 184	2487 ± 118	0.581
Mean Nocturnal Basal Impedance	2323 ± 82	2175 ± 138	2394 ± 101	0.581
Basal impedance at the end of the first quartile of supine time	2323 ± 82	2175 ± 138	2394 ± 101	0.581
Basal impedance at the end of the second quartile of supine time	2639 ± 97	2746 ± 174	2587 ± 117	0.444
Basal impedance at the end of the third quartile of supine time	2728 ± 97	2748 ± 164	2718 ± 120	0.885
Basal impedance at the end of the fourth quartile of supine time	2729 ± 96	2850 ± 178	2671 ± 113	0.383
Nocturnal Basal Impedance (NBI)	2678 ± 81	2835 ± 157	2606 ± 94
All Values are in Ohms

Table: Table 1: Impedance calculated at the times used to calculate the MNBI and Impedance at the beginning of 4 quartiles of sleep

Disclosures:

Ali El Mokahal indicated no relevant financial relationships.

Fahmi Shibli indicated no relevant financial relationships.

Serge Baroud indicated no relevant financial relationships.

Gengqing Song indicated no relevant financial relationships.

Ronnie Fass indicated no relevant financial relationships.

Ali El Mokahal, MD¹, Fahmi Shibli, MD¹, Serge Baroud, MD¹, Gengqing Song, MD¹, Ronnie Fass, MD². P2381 - Variations in Esophageal Nocturnal Impedance Values Throughout the Sleep Period in Gastroesophageal Reflux Disease Patients, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.