Neighborhood deprivation and childhood autism: a nationwide study from Sweden.

OBJECTIVE

To examine whether there is an association between neighborhood deprivation and childhood autism, after accounting for family- and individual-level sociodemographic characteristics.

METHODS

An open cohort of all children aged 2-11 years was followed between January 1, 2000 and December 31, 2010. Childhood residential locations were geocoded and classified according to neighborhood deprivation (an index of low education, low income, unemployment, and receipt of welfare assistance). Data were analyzed by multilevel logistic regression, with family- and individual-level characteristics at the first level and level of neighborhood deprivation at the second level.

RESULTS

During the study period, among a total of 643,456 children, 1699 (0.3%) were diagnosed with childhood autism. Age-standardized cumulative incidence, defined as first registration for childhood autism during the study period, increased with increasing level of neighborhood deprivation. In the study population, 2.2 per 1000 and 3.6 per 1000 children in the least and most deprived neighborhoods, respectively, were diagnosed with childhood autism. Incidence of childhood autism increased with increasing neighborhood-level deprivation across all family and individual-level sociodemographic categories. The odds ratio (OR) for childhood autism for those living in high-deprivation neighborhoods versus those living in low-deprivation neighborhoods was 1.59 (95% confidence interval = 1.35-1.88). High neighborhood deprivation remained significantly associated with odds of childhood autism after adjustment for family- and individual-level sociodemographic characteristics (OR = 1.28, 95% confidence interval = 1.07-1.53, P = 0.007).

CONCLUSIONS

This study is the largest so far on potential neighborhood influences on childhood autism. Our results show that neighborhood deprivation is associated with childhood autism, independently of family- and individual-level sociodemographic characteristics.