Gut microbes mediate the gut-brain axis and research has shown that they may also contribute to depression, anxiety, schizophrenia and other psychiatric conditions. This means that the gut and brain communicate with each other through direct neural connections, hormones or metabolic products. In a new study published in PLOS ONE, researchers found that prolonged antibiotic use in mid-life may be associated with cognitive decline in later life due to gut microbiome changes.
Previous studies have linked chronic antibiotic use with an increased risk of conditions related to chronic inflammation, including obesity, cancer and heart disease. Despite the fact that some gut bacterial species recover after completion of antibiotic treatment, there are changes in overall gut microbial communities and changes in some bacterial genes persist for months to years after drug exposure.
But the evidence linking antibiotic use to cognition is limited. Microbes residing in the gastrointestinal tract are known to induce cognitive side effects.
To go deeper, the study’s researchers included 14,542 US-based nurses as participants of the Nurses Health Study II database, a nationwide cohort study that began in 1989 and looked at risk factors for major chronic diseases in women. examines. The mean age of the participants was 61 years. Participants reported using antibiotics consistently for at least two months. The most common reasons antibiotics were prescribed were respiratory infections, urinary tract infections (UTIs), acne/rosacea, chronic bronchitis, and dental treatment.
They had completed a self-administered psychological test between 2014-2018 using a computer at home. The test consisted of four tasks, including measuring their psychomotor functions and information processing speed. This involves pressing a special key when a playing card is flipped on the screen. The second task involved measuring the women’s alertness and visual attention, in which they press a key when a red card is turned over.
To measure their visual learning and short-term memory, the researchers designed tests where participants were shown playing cards and then asked to remember if they had seen the card before. The researchers then recorded their scores and generated standardized averages based on these various parameters.
The researchers wrote, “We observed that antibiotic use in midlife was significantly associated with later poor scores for global cognition, learning and working memory, and psychomotor speed and attention on cognitive assessments administered 7 years later.” it was done.” Given the profound impact of antibiotic use on the gut microbiome—the gut-brain axis may be a potential mechanism for linking antibiotics to cognitive function.”
In a 2016 study published in the American Academy of Neurology, researchers found that antibiotics may be linked to a severe disruption in brain function called delirium. This state of mental confusion can also cause hallucinations and agitation.
But the researchers of the new PLOS One study note that their findings had limitations. Their antibiotic data did not contain information on specific antibiotic types. In addition, participants’ antibiotic use was based on self-report many years after use and may have been subject to misclassification.