New research from the Telethon Institute for Child Health Research has shown that children with an intellectual disability or autism are up to ten times more likely to be admitted to hospital than unaffected children.
The findings have been published online in BMJ Open.
The research team looked at more than one million hospital admission records from 416,611 Western Australian children born between 1983 and 1999. Children with an intellectual disability or autism were placed into one of five categories and compared with the remainder of the children.
Study leader Dr Helen Leonard said the increased risk of hospitalisation varied from two to ten times that of the rest of the population.
"We expected that children with autism or an intellectual disability would require more stays in hospital but this had not been previously documented," Dr Leonard said.
"We found that the burden is greatest for children with intellectual disability, particularly those with severe intellectual disability (children with an IQ less than 40 where the cause is unknown) where hospital admissions are ten times that of the general population."
The study also showed that compared to unaffected children, those with a known medical cause for the intellectual disability (such as Down or Rett syndrome) were more than seven times more likely to be hospitalised and those with mild/moderate intellectual disability (children with an IQ of 40-70 where the cause is unknown) were three times more likely to require hospital admission.
"Hospital admission rates were not as high for children with autism but still higher than that of the general population," said Dr Leonard.
"Children with autism are twice as likely to require hospitalisation, and for those who also had an intellectual disability, the rate was almost three times higher."
Study co-author Ami Bebbington said many children with these disorders also have other medical conditions such as obesity, epilepsy, sleep or gastrointestinal problems or skin conditions.
"However, we don't really know whether these children are being admitted for the same or different conditions as those without intellectual disability or autism," said Ms Bebbington.
"More research is needed into how these other underlying medical conditions relate to hospital admissions and ways to reduce the need for a hospital visit through primary care.
"With a better understanding of the hospitalisation patterns of these children, services can be better utilised to meet their special needs."
Intellectual disability affects around 143 per 10,000 children and autism spectrum disorders affect around 51 per 10,000 children according to the latest WA population studies.
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