Children who breathe through their mouth, snore, fiddle with their ears and have worse hearing during a cold are more likely to be autistic, according to a new study.
Experts say they found a link between common ear, nose and throat issues with high scores on key autism traits, and with a diagnosis of autism.
The health issues, which also include rarely listening, going red, pus or sticky mucus discharge from ears, were linked with the developmental disorder and poor coherent speech.
However, the team stressed that their study, published in the journal BMJ Open, does not prove these conditions cause autism, or that children with autism are more likely to suffer these illnesses.
Previous studies have also suggested a link between these sorts of infections and autism.
Dr Amanda Hall, honorary senior research fellow at Bristol Medical School and senior lecturer in audiology at Aston University, told the PA news agency: “I think the type of study design doesn’t allow us to say whether it has a causal influence or not.
“I think what it does do is it adds to the pattern of results that have been reported in the literature for a long time that children with autism have different early history than children who aren’t autistic.
“Early medical history – so ear infections and more broadly – is different in autistic children compared with children who don’t have autism.”
She said the team found that common ear and upper respiratory symptoms appear to be more common in children with a subsequent diagnosis of autism or high levels of autism traits.
“However, it is also important to note that these ENT (ear, nose and throat) symptoms are very common in childhood and most children who experience these signs and symptoms do not go on to be diagnosed with autism,” she said.
“For example, of the group of around 1,700 children who snored at age 30 months, most of them (1,660 children) did not get a later diagnosis of autism.”
She said her “take-home” message for parents of autistic children is to “consult with their GP or paediatrician if they have concerns about their child’s ear and hearing”.
The common common ear, nose, and throat issues linked to autism
- Mouth breathing
- Snoring
- Sleep apnoea
Pulling and poking ears
- Ears red and sore
- Pus/mucus from ears
- Hearing worse during cold
- Rarely listens
The researchers used data from the long-term Children Of The 90s study, also known as the Avon Longitudinal Study Of Parents And Children, which has tracked children since birth.
They examined data for more than 10,000 young children who were closely monitored throughout their first four years of life.
Their mothers completed three questionnaires between 18 and 42 months, recording the frequency of different signs and symptoms relating to the upper respiratory system, as well as ear and hearing problems.
They also completed three questionnaires when their children were just over three, nearly six, and nine.
These were designed to pinpoint speech coherence, social and communication issues, repetitive and abnormal behaviours, and sociability – traits which are linked to autism.
Records showing a diagnosis of autism was also used.
Questions asked of mothers included “Has your baby had earache?”, “Does s/he breathe through her mouth rather than through her nose?” and “Does she pull, scratch or poke at her ears?”
Overall, 177 children in the study were found to have a probable diagnosis of autism.
Early evidence of breathing through the mouth, snoring, ear pulling or poking, reddened and sore ears, worse hearing during a cold, and rarely listening, were all more commonly associated with high scores on autism traits, and with a diagnosis of autism.
Pus or sticky discharge from the ears was also associated with autism and with poor coherent speech.
Even when 10 possible environmental factors were taken into account, the findings did not really change.
For example, children with discharge of pus or sticky mucus from ears were over three times more likely to have autism aged 30 months, while those with impaired hearing during a cold were more than twice as likely.
Autistica charity head of research, Dr Amanda Roestorf, told PA: “Over the past 30 years, there has been converging evidence to show that autistic children are likely to have more medical conditions than non-autistic children.
“This study provides new insights into the potential association between early childhood ENT symptoms and autism … Given the issues raised in previous literature, the study findings provide a basis for considering treatment pathways for ENT problems in autistic children in general practice and secondary care.”
She said there were some potential methodological challenges in the study, including the full impact of environmental factors and relying on self-reported data provided by mothers, which may not accurately reflect symptoms.
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