P0431 - An Investigation About the Role of Stimulated and Unstimulated Saliva Cholinesterase Activity and Saliva Flow Rate in Gastroesophageal Reflux Disease vs Healthy Individuals

Sunday, October 22, 2023

3:30 PM – 7:00 PM PT

Location: Exhibit Hall

Has Audio

Presenting Author(s)

Marjan Mokhtare, MD

Iran University of Medical Sciences
Tehran, Tehran, Iran

Award: Presidential Poster Award

Marjan Mokhtare, MD, Mohammad Reza Mirzaii Dizgah, MD
Iran University of Medical Sciences, Tehran, Tehran, Iran

Introduction: Gastroesophageal reflux disease (GERD) is a common worldwide diseases. GERD diagnosis is confirmed by physiologic test and endoscopy which are invasive and expensive. Parasympathetic dysfunction and cholinesterase activity (reflux and reflex pathways) has an etiopathologic role in GERD, non-erosive reflux disease (NERD) and extra-esophageal reflux (EER). This study was purposed to investigate the role of saliva cholinesterase activity in GERD versus healthy participants.

Methods: Thirty patients with GERD-LA class A or B and 30 healthy individuals who were matched in terms of age and gender were included in the study. To get unstimulated saliva, participants pushed their saliva into the tube after 60-90 minutes fasting. To stimulate saliva, volunteers were then requested to chew a piece of natural turpentine for one minute and pushed their saliva. The amount of saliva flow rate was considered by volume (ml)/ duration (minutes). The samples were centrifuged ten minutes. Cholinesterase activity was assessed by photometric method. Each sample was measured at least twice for coefficient of variation (CV) less than 15%. The data were analyzed by Unpaired Student t-test and ROC method.

Results: The mean stimulated saliva cholinesterase activity and flow rate were significantly lower in GERD patients (P=0.001 and p=0.014, respectively). The mean unstimulated saliva cholinesterase activity (P = 0.001) were significantly lesser in GERD patients and the flow rate was not different between groups (P = 0.643). The cutoff point of cholinesterase activity of unstimulated saliva was 225 IU/L (Sensitivity 78% and Specificity 74%; P=0.001) and 134 IU/L (Sensitivity 95% and Specificity 93%; P=0.001) for stimulated saliva in GERD patients. Stimulated saliva cholinesterase activity had significant correlation with saliva flow rate (r= 0.256; P= 0.022).

Discussion: Stimulated saliva cholinesterase activity and flow rate was significantly lower in GERD patients and this test might be considered as a noninvasive diagnostic test. Large sample size studies with measuring pepsin, acid, mucin, and inflammatory cytokines levels to investigate their association with cholinesterase activity in GERD patients and so any association between cholinesterase activity and severity of GERD and EER should be considered.

Figure: Figure 1. Receiver operating characteristics (ROC) curves for the diagnostic value of cholinesterase activity in stimulated and unstimulated saliva of GERD patients.

Variable	Control Group	Case Group	P value
Unstimulated Saliva Cholinesterase Activity(IU/mL)	284 ±13	169 ±30	0.001
Stimulated Saliva Cholinesterase Activity(IU/mL)	245 ±9	40 ±15	0.001
Unstimulated Saliva Flow Rate(mL/min)	0.93 ±0.06	0.90 ±0.02	0.643
Stimulated Saliva Flow Rate(mL/min)	1.33 ±0.07	1.08 ±0.03	0.002
Unstimulated cholinesterase activity Cutoff Point Sensitivity Specificity Area under Curve	- - - -	225 74% 78% 0.736	0.000
Stimulated cholinesterase activity Cutoff Point Sensitivity Specificity Area under Curve	- - - -	134 95% 93% 0.952	0.000

Table: Table 1. Mean salivary levels of cholinesterase activity and salivary flow in patients with gastroesophageal reflux disease (GERD) and healthy individuals, and Cutoff Point, Sensitivity, Specificity, and Area under Curve for stimulated and unstimulated saliva in GERD patients

Data are expressed as Mean ± SD and analyzed with Unpaired student’s t-test

Disclosures:

Marjan Mokhtare indicated no relevant financial relationships.

Mohammad Reza Mirzaii Dizgah indicated no relevant financial relationships.

Marjan Mokhtare, MD, Mohammad Reza Mirzaii Dizgah, MD. P0431 - An Investigation About the Role of Stimulated and Unstimulated Saliva Cholinesterase Activity and Saliva Flow Rate in Gastroesophageal Reflux Disease vs Healthy Individuals, ACG 2023 Annual Scientific Meeting Abstracts. Vancouver, BC, Canada: American College of Gastroenterology.