Wireless pH Capsule Testing: The Effects of Diabetes and Narcotic Use and the Safety of Clopidogrel and Warfarin During Testing

Abstract

Purpose: Wireless pH capsule testing is routinely performed in diabetics (DM), and in patients who use clopidogrel, warfarin and narcotics. Our aim is to evaluate the impact of diabetes and narcotic use on wireless pH monitoring in patients (Pts) either on or off acid suppression and to evaluate the safety of wireless pH monitoring in Pts taking clopidogrel or warfarin. Methods: Data were collected from consecutive Pts referred for wireless pH capsule testing. Demographics, BMI, duration of symptoms, the reason for the test, and the type, dose, and frequency of acid suppression were recorded at the time of wireless pH capsule placement. Charts were reviewed to determine whether the Pt was on narcotics, warfarin, or clopidogrel at the time of the study, and to determine whether the Pt was diabetic (insulin requiring or oral medication). Patients remained on clopidogrel during the study but stopped warfarin 3 days before the test. Standard pH data (# of reflux episodes, # of episodes > 5 minutes, % time with acid reflux, DeMeester score, symptom association probability (SAP)) were calculated and analyzed for Day 1, Day 2 and Total. A study was considered abnormal if the total fraction of time with acid reflux > 5.3%. SAP scores > 95% were considered significant. AEs were monitored by phone call after capsule placement and at the time the receiver was returned. Results: 1754 patients (59% male) with a mean (SD) age of 50 (+/- 13) yrs and a BMI of 28.3 (+/- 7.1) kg/m2 were evaluated. The wireless capsule was placed transorally after manometry in 71% of Pts, while 29% were placed after EGD. The primary reason for testing was reflux symptoms (heartburn and regurgitation) in 74% of Pts, chest pain in 9%, ENT symptoms in 5% and pulmonary symptoms in 5%. Studies were completed off PPI therapy in 69% of Pts. Of those studied on PPI therapy, 35% (n = 187) were on a daily PPI, while 57% (n = 303) were on a twice daily PPI. Clopidogrel was used by 32 Pts (2.3%) and warfarin by 32 (2.3%). No complications occurred in either group. Type II DM was present in 44 (3.2%) of Pts and Type I DM was present in 28 (2%). Chronic narcotic use was identified in 60 Pts (4.4%), while 107 (7.8%) were on p.r.n. narcotics. BMI was the only measure associated with an increased odds of having an abnormal pH test while off PPIs (OR 1.05, 95% CI 1.03-1.07; p <0.02). pH measures in Pts with DM, either on or off PPI therapy, were not different compared to those Pts without diabetes. Conclusion: The results of wireless pH monitoring do not seem to be affected by the use of narcotics or co-existing diabetes. No complications occurred in the group of patients taking clopidogrel or warfarin. Routinely stopping clopidogrel for wireless pH capsule testing may not be necessary.