Several environmental, biological and genetic factors are known to contribute to autism spectrum disorder, a developmental disability caused by differences in the brain. There was no single known cause that could determine autism. However, a new study has found that common ear, nose and throat (ENT) problems and upper respiratory infections in young children may indicate the subsequent risk of autism.

Autism begins before the age of 3 and the symptoms can last throughout a person's life, although sometimes it may improve over time

Common signs of autism

Children diagnosed with autism may lack social communication and interaction skills and have issues like:

  • Avoiding eye contact
  • Failing to respond to name by nine months of age
  • Not sharing interests with others by 15 months
  • Not responding to smile
  • Difficulties sharing an imaginative play

They also may show restricted or repetitive behaviors like:

  • Lining up toys or objects
  • Repeating words or phrases
  • Flapping hands or rocking body
  • Shows obsessive interests and must follow a certain routine

They also show other signs like:

  • Delayed language skills, movement skills or learning skills,
  • Hyperactive, impulsive or inattentive behavior
  • Epilepsy or seizure disorder
  • Unusual eating and sleeping habits
  • Gastrointestinal issues such as constipation
  • Anxiety, stress or excessive worry
  • Lack of fear

Earlier research has shown that ENT conditions, such as ear infections, "glue ear," and sleep-disordered breathing may have a role in the development of autism. However, since most of the evidence was based on health records, there were chances that the findings were biased.

The new study analyzed data from more than 10,000 children, who were participants in a long-term study called the Avon Longitudinal Study of Parents and Children.

The researchers asked the mothers of the participants to fill in three questionnaires when their children were aged 18, 30 and 42 months. The questionnaires recorded the frequency of nine different symptoms relating to the ear, nose, throat, which included breathing through the mouth, snoring, ear pulling or poking, reddened and sore ears, worse hearing during a cold, rarely listening, and sticky discharge from the ears.

The same group was given a separate set of three questionnaires when their children were just over 3, nearly 6, and 9 years old. They recorded issues with speech coherence, social and communication issues and repetitive and abnormal behaviors and sociability, which are characteristic symptoms of autism.

Out of the participants, 177 children – 139 boys and 38 girls – were diagnosed with autism.

Researchers found that children with ENT symptoms showed high scores on each of the four autism traits that they evaluated.

The study does not mean all children who have ear infections will eventually be diagnosed with autism. It also does not indicate all people with autism had upper respiratory infections as a child.

"Most children with signs of ear infection are not autistic so it would not help to screen those with infections," study author Dr. Amanda Hall said. "However, it could be helpful to ensure children with autism are regularly checked for common ear, nose, and throat conditions."

In the evaluated group, around 1,700 children snored at 30 months, and 1,660 of them were not diagnosed with autism later.

Although the study could not conclude if the ENT conditions have a causal role in the development of autistic traits, it adds to evidence that early ear and upper respiratory symptoms are more common in children who are later diagnosed with autism. Researchers believe this could be caused by minor physical anomalies found in individuals with autism.

"One possibility, for example, could be the consequence of the increased prevalence of minor physical anomalies in individuals with autism, including anatomical differences in the structure and/or positioning of the ear, with such differences in ear morphology increasing the risk of ENT conditions," the researchers wrote.

A new study has found that common ear, nose, and throat (ENT) problems and upper respiratory infections in young children may indicate the subsequent risk of autism. pixabay