Treating Gut Microbiome with Probiotics Seen to Aid Cognitive Abilities in Pilot Study

Treating Gut Microbiome with Probiotics Seen to Aid Cognitive Abilities in Pilot Study

A small pilot study found that eight weeks of treatment with probiotics — live microorganisms thought beneficial to the gut microbiota — significantly helped to improve some aspects of cognition in fibromyalgia patients, like impulsive choice and decision-making.

But self-reported improvements in life quality and a lesser sense of depression or anxiety were similar between patients taking the probiotics and those given a placebo — the so-called “placebo effect,” which the researchers suggested might have resulted from an “expectation of symptom improvement.”

The study, “A Pilot Randomized Controlled Trial to Explore Cognitive and Emotional Effects of Probiotics in Fibromyalgia,” was published in the journal Nature Scientific Reports.

Several studies have demonstrated that the balance of the gut microbiome — the bacteria and other microorganisms that compose the digestive tract — has a direct role in regulating such “chores” of the brain as motivation, affection and cognition.

It has been hypothesized that microorganisms in the gut actually regulate brain processes through a “bidirectional communication network” called the gut microbiota—brain axis or GBA.

Scientists are starting to consider GBA as a potential treatment target for disorders linked to problems with the brain and its workings.

Probiotics, or microorganisms that benefit the health of the host organism when administered at appropriate doses, are one way of adjusting the gut’s microbiota.

Recent evidence suggests that probiotic use has the potential to improve the physical, psychological, and cognitive state of patients with an imbalanced gut microbiota, a group that includes people with fibromyalgia.

A pilot, randomized study was opened in Spain to determine whether a multi-species probiotic could be of benefit to fibromyalgia patients, in terms of their cognitive abilities, emotional symptoms, and functional state.

Participants were divided into two groups — those that were treated with probiotics (16 people) and those that were treated with placebo (15) for eight weeks.

Interestingly, results showed that both groups reported a decline in fibromyalgia impact (FIQ) scores (indicating improved functional status) and higher quality of life (SF-36) scores compared to baseline.

Both groups also experienced a reduction in depressive symptoms and urinary cortisol levels (indicating a better physiological response) compared to baseline.

The placebo effect was a likely reason, the researchers said, noting that its impact on studies “has been widely demonstrated in the literature, even in people with FMS [fibromyalgia syndrome].”

But results also showed that two impulsivity constructs of cognition — impulsive choice and decision-making — were significantly improved in the probiotic group compared to the placebo group. These were measured using the two-choice task —a measure of a person’s tendency for immediate gratification, or tendency to choose a small reward over a larger delayed reward — and the Iowa gambling task, which measures risk sensitivity, as defined by the inability to anticipate and reflect on the consequences of a decision.

Specifically, those patients given the probiotics demonstrated significantly fewer impulsive choices than the placebo group after the eight-week treatment, while both groups had similar scores at baseline.

Placebo patients participants also scored significantly worse in emotion-based decision-making task (defined by more damaging choices at the end of a task) after the study’s end compared to its start. The researchers attributed this to an increase in the severity of fibromyalgia symptoms that might drive impulsivity over the study’s length.

“An 8-week multispecies probiotic intervention improves cognition, specifically impulsive choice and decision-making, in a group of patients diagnosed with FMS,” the researchers concluded.

They also suggested “[f]uture studies should investigate the effects of probiotics in combination with other treatments, including dietary changes, in FMS and other clinical populations, as well as the impact of these live organisms on other cognitive functions affected in FMS patients (e.g., cognitive flexibility or working memory).”