Sporebiotics Improve Functional Dyspepsia Symptoms

Will Pass

June 02, 2021

Compared with placebo, sporebiotics significantly reduced postprandial distress, epigastric pain, and several other symptoms of functional dyspepsia, reported lead author Lucas Wauters, MD, PhD, of University Hospitals Leuven (Belgium), and colleagues.

"Acid suppressive or first-line therapy with PPIs [proton pump inhibitors] for functional dyspepsia has limited efficacy and potential long-term side effects," the investigators reported at the annual Digestive Disease Week® (DDW). "Spore-forming bacteria or sporebiotics may be effective for postprandial distress and epigastric pain or burning symptoms, offering benefits which may differ in relation to PPI intake."

Sporebiotics Improve Variety of Symptoms

To test this hypothesis, the investigators recruited 68 patients with functional dyspepsia who had similar characteristics at baseline. Half of the participants (n = 34) were taking PPIs.

Patients were randomized in a 1:1 ratio to receive 2.5 x 109 CFU of Bacillus coagulans MY01 and B. subtilis MY02 twice daily for 8 weeks, or matching placebo. Following this period, an additional 8-week open-label regimen was instituted, during which time all patients received sporebiotics. Throughout the study, a daily diary was used to self-report symptoms.

The primary outcome, measured at 8 weeks, was clinical response, defined by a decrease in weekly postprandial distress symptoms greater than 0.7 among patients who had a baseline score greater than 1.0. Secondary outcomes included change in postprandial distress symptoms greater than 0.5 (minimal clinical response), as well as changes in cardinal epigastric pain, cardinal postprandial distress, and other symptoms. At baseline and 8 weeks, patients taking PPIs underwent a 14C-glycocolic acid breath test to detect changes in small intestinal bacterial overgrowth.

At 8 weeks, a clinical response was observed in 48% of patients taking sporebiotics, compared with 20% of those in the placebo group (P = .03). At the same time point, 56% of patients in the treatment group had a minimal clinical response versus 27% in the control group (P = .03).

Spore-forming probiotics were also associated with significantly greater improvements in cardinal postprandial distress, cardinal epigastric pain, postprandial fullness, and upper abdominal pain. A trend toward improvement in upper abdominal bloating was also seen (P = .07).

Among patients taking PPIs, baseline rates of positivity for bile acid breath testing were similar between those in the sporebiotic and placebo group, at 18% and 25%, respectively (P = .29). After 8 weeks, however, patients taking spore-forming probiotics had a significantly lower rate of bile acid breath test positivity (7% vs. 36%; P = .04), suggesting improvements in small intestinal bacterial overgrowth.

In the open-label portion of the trial, patients in the treatment group maintained improvements in postprandial distress. Patients who switched from placebo to sporebiotics had a significant reduction in postprandial distress symptoms.

At 8 weeks, sporebiotics were associated with a trend toward fewer side effects of any kind (16% vs. 33%; P = .09), while rates of GI-specific side effects were comparable between groups, at 3% and 15% for sporebiotics and placebo, respectively (P = .2)."Spore-forming probiotics are effective and safe in patients with functional dyspepsia, decreasing both postprandial distress and epigastric pain symptoms," the investigators concluded. "In patients [taking PPIs], sporebiotics decrease the percentage of positive bile acid breath tests, suggesting a reduction of small intestinal bacterial overgrowth."

Results Are Promising, but Big Questions Remain

Pankaj Jay Pasricha, MBBS, MD, vice chair of medicine innovation and commercialization at Johns Hopkins and director of the Johns Hopkins Center for Neurogastroenterology, Baltimore, called the results "very encouraging."

"This [study] is the first of its kind for this condition," Pasricha said in an interview. "It will be very interesting to see whether others can reproduce these findings, and whether [these improvements] are sustained beyond the first few weeks or months."

He noted that determining associated mechanisms of action could potentially open up new lines of therapy, and provide greater understanding of pathophysiology, which is currently lacking.

"We don't fully understand the pathophysiology [of functional dyspepsia]," Pasricha said. "If you don't understand the pathophysiology, then it's difficult to identify the right molecular target to address the root cause. Instead, we use a variety of symptomatic treatments that aren't actually addressing the root cause, but studies like this may help us gain some insight into the cause of the problem, and if it is in fact a fundamental imbalance in the intestinal microbiota, then this would be a rational approach."

It's unclear how sporebiotics may improve functional dyspepsia, Pasricha noted. He proposed three possible mechanisms: the bacteria could be colonizing the intestine, they could be releasing products as they pass through the intestine that have a therapeutic effect, or they may be altering bile acid metabolism in the colon or having some other effect there.

"It's speculative on my part to say how it works," Pasricha said. "All the dots remain to be connected. But it's a good start, and an outstanding group of investigators." Wauters and colleagues reported no conflicts of interest. Pasricha disclosed a relationship with Pendulum Therapeutics.

This article originally appeared on MDedge.com , part of the Medscape Professional Network.


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