Large-Scale Study Reveals Strange Link Between Antibiotics and Cognitive Decline


A study of a total of 14,542 women found a still unexplained link between taking antibiotics for at least two months in their 40s and lower assessments of cognitive scores taken several years later.

The team behind the research, led by epidemiologists from Harvard Medical School in Massachusetts, say it shows how important it is to carefully monitor antibiotic use – and also how important it is is important that we understand the connection between what happens in our intestines (which antibiotics can affect) and what happens in our brain.

Many previous studies have highlighted the link between the gut microbiome and the brain, but it’s unclear exactly what the relationship might be. This new research adds more data points in a much-needed area of ​​study.

“In a cohort of over 14,000 women, we observed that midlife antibiotic use was significantly associated with lower later scores for global cognition, learning, and working memory, as well as psychomotor speed and attention,” the researchers write in their paper.

“To our knowledge, our study represents the first large study of long-term chronic antibiotic use and related cognition.”

The women in the cohort (a long-term chronic disease research project called Nurses Health Study) had taken antibiotics for a variety of reasons, including respiratory infections, dental problems, acne, and urinary tract infections.

For those taking antibiotics, the resulting drop in brain power across different categories of learning, response, and memory is equivalent to about three or four years of normal aging, the data shows.

Cognitive ability was assessed on average seven years after the start of antibiotic use, through an online test that participants completed at home. The test includes four different tasks in total, designed to measure different aspects of cognitive performance.

“This relationship was associated with longer duration of antibiotic use and persisted after adjusting for many potential confounders,” write the researchers.

As usual with studies like this, the link is not enough to prove causation – that is, the data does not show that it is definitely the use of antibiotics that leads to a decrease. cognition. It’s possible that the conditions the antibiotics were meant to treat, rather than the antibiotics themselves, caused this small decline in cognition, for example.

However, there is enough here to suggest that more research is certainly warranted. The limitations of this study are that it did not examine any particular type of antibiotic and relied on self-reporting of antibiotic use. However, the large sample size and the consideration of other variables, including diet and other medications, increase its value.

Investigations into the link between antibiotics, the gut microbiome and brain function continue tobut to date, this is one of the best studies we have of potential long-term effects in adult humans.

“Given the profound effect of antibiotic use on the gut microbiome – with previous studies showing alterations in functional potential two and four years after antibiotic exposure – the gut-brain axis could be a possible mechanism for linking antibiotics to cognitive function”, write the researchers.

The research has been published in PLOS A.


About Author

Comments are closed.