The efficacy of antibiotics has come under scrutiny in recent years amid growing concerns that their overuse has contributed to bacteria developing resistance and the emergence of deadly so-called superbugs.
A team of scientists led by researchers at Uppsala University in Sweden has come up with more evidence of the potential ill effects of too much antibiotic use, warning that they can lead to gut microbiome alterations that last for between four and eight years.
“Even a single course of treatment with certain types of antibiotics leaves traces,” says study first author and postdoctoral researcher Dr Gabriel Baldanzi.
“The effect of antibiotics on the gut microbiome may persist for several years,” the team says in a paper published in the journal Nature Medicine and based on an examination of patient data covering almost 15,000 people and going back eight years.
“We can see that antibiotic use as far back as four to eight years ago is linked to the composition of a person’s gut microbiome today,” Dr Baldanzi says.
“Antibiotics are known gut microbiome disruptors, but their long-term consequences remain underexplored,” the team says in the paper, explaining why they carried out the research.
The researchers also sought to better understand the links shown in prior epidemiological studies between high antibiotic use and the likelihood of type 2 diabetes and gastrointestinal infections.
“The reasons for these observations are not fully understood, but changes in the gut microbiome are thought to play a role,” the team says, adding that the links point to “questions about the long-term footprint of antibiotics on the gut microbiome”.
The strongest links were found for antibiotics such as fluoroquinolones, which are used against life-threatening diseases and are known to have side effects, and flucloxacilli, which people often take for skin conditions.
But one of the most widely used antibiotics, penicillin V, appears to have no more than “small and short-lasting microbiome changes”, the team says. – dpa
