Scientists connect the childhood microbiome with the development of autism and ADHD

Certain changes in the childhood gut microbiome may correlate with future diagnoses of neurodevelopmental disorders such as autism and ADHD (attention deficit hyperactivity disorder)according to a report released this Thursday by the University of Florida (UF).

The study, the first of its kind, shows that changes in the childhood microbiome (microbes that colonize the intestinal tract and play an important role in the development of the immune system and health) show a correlation with future diagnoses of neurodevelopmental disorders .

Changes in the microbiome that are also related to environmental factors and even common treatments for ear infections during childhood, indicates the study carried out by scientists from the UF Institute of Agricultural and Food Sciences (UF/IFAS) and the universities from Linköping and Örebro, in Sweden.

The study used data accumulated over 20 years from 16,440 Swedish children who were part of the program called All Babies in Southeast Sweden (ABIS).

Of this total of children, 1,197, equivalent to 7.28%, developed some neurodevelopmental disorder.

In the analyzes of the first five years of children’s lives, biological and environmental factors were examined that could influence the presence, decrease or absence of certain bacteria linked to the development of conditions such as autism, ADHD, intellectual disability or mental disorders. speech.

The research team found “significant differences in the gut microbiomes of infants who later received diagnoses of neurodevelopmental disorders.” These differed depending on the diagnosis, but common patterns were also observed, the study notes.

Many bacteria that promote gut health, including Akkermansia, Bifidobacterium, Ruminococcus, and Faecalibacterium, ““They were deficient” in infants with future diagnoses of neurodevelopmental disorders.

This correlation with future diagnosis remained strong, even after researchers accounted for certain confounding factors such as mode of delivery, diet, psychosocial vulnerability, and toxic exposures.

One of the most surprising findings of the study was the correlation found between “neurodevelopmental disorders and the treatment of ear infections with the use of antibiotics such as penicillin” in early childhood, said Eric Triplett, professor and chair of the UF/IFAS Department of Microbiology and Cellular Sciences, one of the study’s authors.

According to the study’s findings, children who experienced three or more ear infections treated with penicillin, from birth to age 5, were 3.89 times more likely to develop a speech disorder, 3.27 times more likely to develop a speech disorder, and 3.27 times more likely to develop a speech disorder. high rate of developing ADHD and 2.44 times higher of developing an intellectual disability.

In contrast to children who did not experience ear infections, the microbiomes of those who developed neurodevelopmental disorders years later contained higher levels of Citrobacter, a genus of bacteria associated with inflammation, as well as lower levels of Coprococcus, a genus of bacteria associated with positive mental health.

Researchers suspect that penicillin increases levels of Citrobacter and coprococcus in the microbiome.

“We’re not trying to say that antibiotics are necessarily a bad thing,” clarified Angelica Ahrens, UF/IFAS research scientist and co-author of the study.

However, Ahrens noted, “Excessive use may have negative effects on the microbiome, and for some children, for whatever reason, their microbiome may not recover as easily.”

The study also found that maternal smoking during pregnancy led to children being 3 times more likely to develop a neurodevelopmental disorder.

When mothers smoked more than 15 cigarettes a day, secondhand smoke made their children 4.88 times more likely to develop ADHD, and when fathers smoked more than 15 cigarettes a day, children were 3.47 times more likely to develop ADHD. times more likely to develop autism.

It may interest you