Background: Ambulatory esophageal pH monitoring is the method used most widely to quantify gastroesophageal reflux. The degree of gastroesophageal reflux may potentially be underestimated if the resting gastric pH is high. Normal subjects and symptomatic patients undergoing 24-h pH monitoring were studied to determine whether a relationship exists between resting gastric pH and the degree of esophageal acid exposure.
Methods: Normal volunteers (n = 54) and symptomatic patients without prior gastric surgery and off medication (n = 1,582) were studied. Gastric pH was measured by advancing the pH catheter into the stomach before positioning the electrode in the esophagus. The normal range of gastric pH was defined from the normal subjects, and the patients then were classified as having either normal gastric pH or hypochlorhydria. Esophageal acid exposure was compared between the two groups.
Results: The normal range for gastric pH was 0.3-2.9. The median age of the 1,582 patients was 51 years, and their median gastric pH was 1.7. Abnormal esophageal acid exposure was found in 797 patients (50.3%). Hypochlorhydria (resting gastric pH >2.9) was detected in 176 patients (11%). There was an inverse relationship between gastric pH and esophageal acid exposure (r = -0.13). For the patients with positive 24-h pH test results, the major effect of gastric pH was that the hypochlorhydric patients tended to have more reflux in the supine position than those with normal gastric pH.
Conclusion: There is an inverse, dose-dependent relationship between gastric pH and esophageal acid exposure. Negative 24-h esophageal pH test results for a patient with hypochlorhydria may prompt a search for nonacid reflux as the explanation for the patient's symptoms.
López-Alonso M, Moya MJ, Cabo JA, Ribas J, del Carmen Macías M, Silny J, Sifrim D. López-Alonso M, et al. Pediatrics. 2006 Aug;118(2):e299-308. doi: 10.1542/peds.2005-3140. Epub 2006 Jul 10. Pediatrics. 2006. PMID: 16831894
Shay S, Tutuian R, Sifrim D, Vela M, Wise J, Balaji N, Zhang X, Adhami T, Murray J, Peters J, Castell D. Shay S, et al. Am J Gastroenterol. 2004 Jun;99(6):1037-43. doi: 10.1111/j.1572-0241.2004.04172.x. Am J Gastroenterol. 2004. PMID: 15180722
Katzka DA, Gideon RM, Castell DO. Katzka DA, et al. Am J Gastroenterol. 1998 Aug;93(8):1236-42. doi: 10.1111/j.1572-0241.1998.00402.x. Am J Gastroenterol. 1998. PMID: 9707044
Vardar R, Keskin M. Vardar R, et al. Turk J Gastroenterol. 2017 Dec;28(Suppl 1):S16-S21. doi: 10.5152/tjg.2017.06. Turk J Gastroenterol. 2017. PMID: 29199161 Review.
Streets CG, DeMeester TR. Streets CG, et al. J Clin Gastroenterol. 2003 Jul;37(1):14-22. doi: 10.1097/00004836-200307000-00007. J Clin Gastroenterol. 2003. PMID: 12811203 Review.
Youssefnia A, Pierre A, Hoder JM, MacDonald M, Shaffer MJB, Friedman J, Mehler PS, Bontempo A, da Silva FCN, Chan ED. Youssefnia A, et al. J Thorac Dis. 2022 Sep;14(9):3575-3597. doi: 10.21037/jtd-22-410. J Thorac Dis. 2022. PMID: 36245600 Free PMC article. Review.
Kuo YC, Yu LY, Wang HY, Chen MJ, Wu MS, Liu CJ, Lin YC, Shih SC, Hu KC. Kuo YC, et al. World J Gastrointest Oncol. 2022 Jan 15;14(1):55-74. doi: 10.4251/wjgo.v14.i1.55. World J Gastrointest Oncol. 2022. PMID: 35116103 Free PMC article. Review.
Jun YK, Kim JW, Kim BG, Lee KL, Jung YJ, Kim W, Park HS, Lee DH, Koh SJ. Jun YK, et al. PLoS One. 2022 Jan 21;17(1):e0261448. doi: 10.1371/journal.pone.0261448. eCollection 2022. PLoS One. 2022. PMID: 35061730 Free PMC article.
Thompson CM, Kirman CR, Hays SM, Suh M, Harvey SE, Proctor DM, Rager JE, Haws LC, Harris MA. Thompson CM, et al. J Appl Toxicol. 2018 Mar;38(3):351-365. doi: 10.1002/jat.3545. Epub 2017 Oct 24. J Appl Toxicol. 2018. PMID: 29064106 Free PMC article.
Kishikawa H, Kimura K, Ito A, Arahata K, Takarabe S, Kaida S, Kanai T, Miura S, Nishida J. Kishikawa H, et al. PLoS One. 2017 Jan 20;12(1):e0170416. doi: 10.1371/journal.pone.0170416. eCollection 2017. PLoS One. 2017. PMID: 28107506 Free PMC article.
