Prevalence and presentation of lactose intolerance and effects on dairy product intake in healthy subjects and patients with irritable bowel syndrome.

Abstract

BACKGROUND & AIMS:

The effects of lactase deficiency on digestive symptoms and diet in patients with irritable bowel syndrome (IBS) have not been well defined. We assessed lactose absorption and tolerance and the intake of dairy products in healthy volunteers (controls) and patients with diarrhea-predominant IBS (D-IBS).

METHODS:

Sixty patients diagnosed with D-IBS at the Sir Run Run Shaw Hospital, Hangzhou, China and 60 controls were given hydrogen breath tests to detect malabsorption and intolerance after administration of 10, 20, and 40 g lactose in random order 7-14 days apart; participants and researchers were blinded to the dose. We assessed associations between the results and self-reported lactose intolerance (LI).

RESULTS:

Malabsorption of 40 g lactose was observed in 93% of controls and 92% of patients with D-IBS. Fewer controls than patients with D-IBS were intolerant to 10 g lactose (3% vs 18%; odds ratio [OR], 6.51; 95% confidence interval [CI], 1.38-30.8; P = .008), 20 g lactose (22% vs 47%; OR, 3.16; 95% CI, 1.43-7.02; P = .004), and 40 g lactose (68% vs 85%; OR, 2.63; 95% CI, 1.08-6.42; P = .03). H(2) excretion was associated with symptom score (P = .001). Patients with D-IBS self-reported LI more frequently than controls (63% vs 22%; OR, 6.25; 95% CI, 2.78-14.0; P < .001) and ate fewer dairy products (P = .040). However, self-reported LI did not correlate with results from hydrogen breath tests.

CONCLUSIONS:

The risk of LI is related to the dose of lactose ingested and intestinal gas production and is increased in patients with D-IBS. Self-reported LI, but not objective results from hydrogen breath tests, was associated with avoidance of dairy products.

• Authors: Jianfeng Yang, Yanyong Deng, Hua Chu, Yanqun Cong, Jianmin Zhao, Daniel Pohl, Benjamin Misselwitz, Michael Fried, Ning Dai, Mark Fox
• Journal: Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association (Clin Gastroenterol Hepatol) Vol. 11 Issue 3 Pg. 262-268.e1 (Mar 2013) ISSN: 1542-7714 [Electronic] United States
• PMID: 23246646 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

Topics

• Adult
• Breath Tests
• China
• Dairy Products
• Feeding Behavior
• Female
• Humans
• Irritable Bowel Syndrome (complications)
• Lactose Intolerance (complications, epidemiology, pathology)
• Male
• Middle Aged