aetiological and risk factors
Last edited 02/2018 and last reviewed 07/2022
- genetic component - risk in the siblings of autistic children is 3 or 4 times higher than in the general population; more common in boys than girls (approximately 4:1).
- organic cause is suggested by the development of seizures in some 40% of these children when they reach adolescence.
Kanner in his original description of the condition in 1943 suggested that the behaviour of the autistic child was a response to abnormalities in the parents, characterised as cold, detached and 'obsessive'. These ideas have not been substantiated by research.
Autism is associated with:
- the fragile X syndrome
- Rett's syndrome
NICE note factors associated with an increased prevalence of autism (1)
- a sibling with autism
- birth defects associated with central nervous system malformation and/or
dysfunction, including cerebral palsy
- gestational age less than 35 weeks
- parental schizophrenia-like psychosis or affective disorder
- maternal use of sodium valproate in pregnancy
- a learning (intellectual) disability
- attention deficit hyperactivity disorder
- neonatal encephalopathy or epileptic encephalopathy, including infantile
- chromosomal disorders such as Down's syndrome
- genetic disorders such as fragile X
- muscular dystrophy
- tuberous sclerosis