General anesthesia in early childhood and possible association with autism: a population-based matched cohort study.

This large study looked at whether children who had general anesthesia (being put to sleep for surgery) before age 5 were more likely to be diagnosed with autism. They compared over 400,000 children who had anesthesia with over 1 million who didn't. Children who had anesthesia were about 60% more likely to be diagnosed with autism later. However, this doesn't prove anesthesia causes autism - it could be that children needing surgery have other health conditions that increase autism risk.

This population-based cohort study examined the potential association between general anesthesia exposure in early childhood (ages 0-5) and autism spectrum disorder development. The study included 401,750 children exposed to general anesthesia compared with 1,187,796 unexposed children between 2001-2014. Using propensity score matching across 49 variables, researchers found autism/ASD was more common in exposed children (1.65% vs 0.98%). After adjustment, children exposed to general anesthesia showed a 62% increased risk of autism/ASD (RR 1.62, 95% CI: 1.57-1.67).

While statistically significant, the authors emphasize this association does not establish causation and future research is needed to determine whether anesthesia directly causes autism or if other factors explain the relationship.

Healthcare providers should be aware of this association when counseling families about pediatric procedures requiring anesthesia. However, established medical need for surgery should not be deferred based on autism risk concerns. Further research needed to clarify whether association reflects causation or confounding by underlying medical conditions requiring surgical intervention.

Study design cannot establish causation. The association may be due to underlying medical conditions requiring surgery rather than anesthesia itself. Confounding factors may not be fully controlled despite propensity score matching. Long-term follow-up duration and autism diagnostic methods not specified in abstract.

In experimental animal studies, exposure to general anesthesia in early childhood may results in changes in infant brain morphology and behavior, potentially leading to the development of autistic behaviors in the long-term. However, in clinical studies the role of exposure to general anesthesia in early childhood and the risk of autism is unknown. This is a population-based cohort study including all children aged 0-5 years of age exposed to general anesthesia between 2001 and 2014 and a corresponding matched population without such an exposure. Propensity score calculation was based on 49 variables (including age of parents, malformations, APGAR Score, and family income, among others).

Quasi-Poisson regression was used to estimate risk ratios (RRs) with 95% confidence intervals (CIs) for the association between exposure to general anesthesia and autism or autism spectrum disorder. In total, 401,750 children exposed to general anesthesia were compared with 1,187,796 unexposed individuals. Autism or autism spectrum disorder were more common in the children exposed to general anesthesia as compared to unexposed children (1.65% and 0.98%, respectively, P<0.01). There was a statistically significant higher risk of autism or autism spectrum disorder in children exposed to general anesthesia as compared to unexposed children also after propensity score adjustment (RR 1.62, 95% CI: 1.57-1.67).

Exposure to general anesthesia in early childhood was associated with an increased risk of autism or autism spectrum disorder. Future studies are needed to asses if general anesthesia may cause autism or if the association is due to other factors.