By Bruce Sylvester
SAN DIEGO -- October 30, 2009 -- Prolonged use of acid suppression medication appears to be linked to an increased risk of small intestinal bacterial overgrowth (SIBO), according to a study presented here at the American College of Gastroenterology (ACG) 74th Annual Scientific Meeting.
"We found that patients on prolonged acid suppression, such as with proton pump inhibitors and histamine blockers, are more likely to be associated with a positive test for small intestinal overgrowth," said Walter Chan, MD, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, on October 27.
"This finding applies to patients who are not otherwise showing any other risk factors for bacterial overgrowth, such as surgery, diabetes, or other gastrointestinal dysmotility."
The investigators retrospectively evaluated the records of adults who underwent a lactulose breath test at Brigham and Women's Hospital between September 2008 and April 2009. They excluded patients with abdominal surgeries, chronic pancreatitis, gastrointestinal dysmotility, anatomical abnormalities, inflammatory bowel disease, or immunosuppression.
They identified 108 eligible patients (81% female; median age, 46.5 years). The acid suppression subgroup (n = 43) included patients who had used an acid suppression drug for >=2 months prior to the lactulose breath test. The control subgroup (n = 65) reported no acid suppressive drug use prior to the lactulose breath test.
There were no differences in baseline patient characteristics for age, gender, or symptoms between the groups.
Dr. Chan said that symptomatic patients using acid suppression drugs showed a higher rate of positive lactulose breath testing for SIBO than controls (OR [odds ratio] = 2.311; P = .019).
In addition, a higher proportion of patients with SIBO in the acid suppression group were mixed hydrogen-methane producers, compared with the control group (OR = 6.56, P = .03). He noted that this finding suggests that acid suppression might promote the growth of a variety of bacterial species.
The investigators found no differences in the proportion of hydrogen and methane producers between the acid suppression and control groups.
They concluded that prolonged acid suppression might predispose otherwise healthy persons to SIBO, and that discontinuation of acid suppression should be considered for these patients, especially in patients with recurrent SIBO.
[Presentation title: Chronic Use of Acid Suppression Medication Is Associated With Clinically Significant Small Intestinal Bacterial Overgrowth. Abstract 944]
E-Mail this DGDispatch to a colleague
