Spore-forming probiotics may help alleviate pain and discomfort in functional dyspepsia patients, a preliminary study suggests.

Researchers in Belgium assessed the effects of Bacillus coagulans MY01 plus B. subtilis MY02 versus placebo in 68 functional dyspepsia patients who were on or off proton-pump inhibitors.

Their findings, published in the Lancet Gastroenterology & Hepatology, showed that probiotic patients were twice as likely to report improved postprandial distress syndrome (PDS) symptoms than those on placebo after eight weeks of treatment, with 48% achieving a ≥ 0.7 PDS score reduction (baseline score: ≥1 out of 4) on the Leuven Postprandial Distress Scale (RR: 1.95, 95% CI: 1.07–4.11, P = 0.028), the authors wrote.

These improvements persisted at 16 weeks and were observed in patients who switched from placebo to probiotics.

Proton-pump inhibitor-use did not significantly affect probiotic responses.

“Changes in immune activation and intestinal microbiota are potential underlying mechanisms of spore-forming probiotics,” the study authors suggested.

Though microbe diversity didn’t change between probiotic and placebo groups, probiotic patients had more Faecalibacterium, Roseburia and bacteria in the Leuconostocaceae family, and those on proton-pump inhibitors had less bacterial overgrowth, they found.

The researchers saw a proportional decrease in T-helper 17 cell signalling with increasing Faecalibacterium abundance and therefore associated these changes with probiotic efficacy.

Probiotic treatment was safe compared with placebo, with similar incidence of all and gastrointestinal-specific adverse events observed, they wrote.

Currently, “first-line therapy for functional dyspepsia is acid suppression with proton-pump inhibitors and although guidelines advise against dose escalation, inappropriate use of proton-pump inhibitors, even in the absence of clinical benefit, is frequently reported,” they noted.

Long-term use of PPIs has been associated with increased risk of enteric infection, including with C. difficile, and changes in faecal microbiota and dysbiosis.

Although further studies are needed to strengthen evidence for spore-forming probiotics in functional dyspepsia, the researchers’ said their data highlighted the potentially beneficial immune and microbial changes, which could provide insights into possible underlying mechanisms as future predictors or treatment targets.

“Treatment with spore-forming probiotics can be considered as monotherapy or as add-on to proton-pump inhibitors in patients with functional dyspepsia with refractory symptoms,” they suggested.

Additionally, their endospores are gastric-acid resistant and offer high stability and long shelf life, making them advantageous over traditional probiotic supplements, they added.

In an accompanying commentary article, Australian researchers said the findings served as a proof of concept that modulation of microbial and immune homoeostatic balance is an effective therapeutic option for the management of functional dyspepsia.

However “it remains to be seen if spore-forming probiotic cocktails have long-term efficacy in symptom management for functional dyspepsia, and further characterisation of the immune and microbial profiles at the gastroduodenal level is required to establish localised response,” said the authors led by Dr Grace Keely of the Centre of Research Excellence in Digestive Health, Newcastle University, NSW.