. Author manuscript; available in PMC: 2016 Sep 1.

Published in final edited form as: Am J Gastroenterol. 2015 Aug 25;110(9):1339–1346. doi: 10.1038/ajg.2015.220

Table 3.

Large bowel intraluminal pH levels according to IBS subtype

	C-IBS (n=13)	D-IBS (n=14)	M-IBS (n=12)	U-IBS (n=8)	HC (n=10)
Q1 Colonic pH	6.4±0.5	6.7±0.7	6.4±0.5	5.9±0.3^a	6.8±0.4
Q2 Colonic pH	7.0±0.9	6.9±0.8	6.5±0.6	6.5±0.4	7.1±0.5
Q3 Colonic pH	7.1±0.8	7.0±0.6	7.1±0.9	6.7±0.8	7.5±0.6
Q4 Colonic pH	7.3±0.8	7.3±0.7	7.2±1.0	7.0±0.7	7.8±0.8
Total Colonic pH	7.0±0.7	7.0±0.6	6.8±0.7	6.4±0.6^b	7.3±0.5

IBS; irritable bowel syndrome, C-IBS; constipation-predominant IBS, D-IBS; diarrhea- predominant IBS, M-IBS; mixed type IBS, U-IBS; unspecified type IBS, HC; healthy control, Q; quartile

P < 0.05, compared to Q1 colonic pHs of D-IBS and HC;

P < 0.05, compared to total colonic pH of HC

The data are presented as mean ± standard deviation.