Category: Autism

Autism spectrum disorder is a developmental disorder that affects behaviour, social interaction and learning.

Acetaminophen — also known as Tylenol (or paracetamol outside the US) — is linked to autism and ADHD, a study suggests.

Children exposed to higher levels of acetaminophen in the womb were at almost four times the risk of developing autism.

Acetaminophen was linked to almost three times the risk of attention-deficit hyperactivity disorder (ADHD) when they were tested at around nine-years-old.

Autism spectrum disorder is a developmental disorder that affects behaviour, social interaction and learning.

Classic signs of autism include more limited and repetitive play, less name response, less social smiling, less babbling and limited gesture use.

ADHD is characterised by impulsiveness or hyperactivity
and serious problems maintaining attention on one task.

Many children continue to experience the symptoms of ADHD into adulthood.

The results come from a study of 996 births in the US city of Boston.

Blood was taken from the umbilical cord and analysed for levels of acetaminophen and its byproducts.

Around nine years later 6.6 percent had been diagnosed with autism spectrum disorder and 25.8 percent with ADHD.

Researchers then compared children with the lowest levels of acetaminophen in their umbilical cord blood at birth to those with the highest levels.

The results showed that high levels of acetaminophen increased the risk of developing autism by 3.62 times.

For ADHD, those exposed to the highest levels of ADHD were at 2.86 times the risk of developing the condition.

As ever, with this type of research, though, correlation not equal causation.

However, several studies have linked acetaminophen to autism.

Professor Andrew Shennan, an obstetrician at King’s College London, who was not involved in the study, said:

“Paracetamol is a recommended drug for use in pregnancy and will be commonly used.

This type of uncontrolled study does not imply paracetamol use causes autism, as the reason for taking paracetamol may be the issue rather than the drug itself, and a mechanism for it to cause harm is not clear.”

Professor Stephen Evans, a drug safety expert, who was also not involved in the study, said:

“In general, advice has always been to avoid or limit most drugs in pregnancy if possible, but some drugs are required for a mother’s health.

Avoiding paracetamol when it is not needed is sensible and has always been the case, but millions of women with perfectly normal children will also have taken paracetamol during pregnancy.

The results of this study should not raise anxiety in pregnant women.”

The study was published in JAMA Psychiatry (Ji et al., 2019).

The link between autism and early death appears to be mostly due to natural causes.

Having either ADHD or autism comes with a higher risk of dying early, a large study finds.

According to a review of the results of 27 separate studies, people with autism or ADHD are at double the risk of an early death.

The causes of death are both natural and unnatural.

Natural causes of death include seizures and cardiac events, while unnatural deaths include accidents and suicide.

ADHD and early death

ADHD, which affects around 5 percent of people, appears to be particularly strongly linked to unnatural deaths.

People with ADHD are at a high risk of death from accidents, a previous study on the same subject found (Dalsgaard et al., 2015)

Earlier diagnosis, though, tended to be a protective factor.

Those not diagnosed with ADHD until after they were 18 were at four times the risk of an early death, with females being particularly vulnerable.

Dr Søren Dalsgaard, the study’s first author, said:

 “Our findings emphasise the importance diagnosing ADHD early, especially in girls and women, and treating any co-existing antisocial and substance use disorders.

It is however important to emphasise that although the relative risk of premature death is increased in ADHD, the absolute risk is low.”

Autism and early death

The link between autism and early death appears to be mostly due to natural causes.

For example, people with autism are more likely to suffer from other mental health problems like depression, anxiety, eating disorders, conduct and tic disorders.

People with these problems are also more likely to be sedentary, to take little exercise, to be obese and have heart disease and other medical problems.

Professor Stephen Faraone, an expert on ADHD and related disorders, said:

“Although talk of premature death will worry parents and patients, they can seek solace in the knowledge that the absolute risk for premature death is low and that this and other risks can be greatly reduced with evidenced-based treatments for the disorder.”

The study was published in the journal JAMA Pediatrics (Catalá-López et al., 2022).