Migration and risk of intellectual disability with and without autism: A population-based cohort study

Maternal Migration, Prenatal Stress and Child Autistic Traits: Insights From a Population-Based Cohort Study

OBJECTIVE

There is emerging evidence for an increased prevalence of autism in children of mothers with a migration background. To date, the mechanisms underlying this relationship are poorly understood. We investigated whether prenatal stress exposure mediates the association between maternal migration and child autistic traits, assessing first- and second-generation migrant mothers in the Netherlands and their children.

METHOD

The study was embedded in the prospective population-based Generation R cohort. Of the 4,727 participants, 1,773 mothers (38%) had a migration background. Prenatal stress was assessed using questionnaires related to stressful life events, family functioning, self-esteem, long-lasting difficulties, symptoms of psychopathology, social support, and perceived discrimination. Autistic traits were measured at age 6 years with the parent-reported Social Responsiveness Scale exclusively. Longitudinal multiple mediation analyses were performed. Analyses were stratified by migration origin (Europe and outside Europe) because of differences in migration characteristics.

RESULTS

Maternal migration background was associated with more experienced stress and with higher child autistic trait scores (Europe: mean = 0.42, SD = 0.25; outside Europe: mean = 0.50, SD = 0.24) compared to no migration background (Netherlands: mean = 0.38, SD = 0.23; both p < .01). Prenatal stress, especially perceived discrimination and maternal psychopathology, accounted for up to half of the total effect of maternal migration, which remained after adjusting for sociodemographic factors (Bindirect = 0.035, 95% CI = 0.027, 0.043, Btotal = 0.074).

CONCLUSION

Stress during pregnancy mediated the association between maternal migration status and child autistic traits. Future research should focus on early interventions to assess whether reducing prenatal stress exposure among women with a migration background can result in lower offspring autistic traits.

PLAIN LANGUAGE SUMMARY

There is emerging evidence that autism is more common in children of mothers with a migration background, but it remains unclear why. This large, community-based longitudinal study followed 4,727 pregnant women, of whom 1,773 had a migration background, in the Netherlands. The authors found that mothers with a migration background reported more stress during pregnancy and more autistic traits in their children 6 years later than mothers without a migration background. Stress during pregnancy, especially perceived discrimination and maternal psychopathology, accounted for up to half of the total effect of maternal migration on child autistic traits.

DIVERSITY & INCLUSION STATEMENT

We worked to ensure that the study questionnaires were prepared in an inclusive way. We worked to ensure sex and gender balance in the recruitment of human participants. We worked to ensure race, ethnic, and/or other types of diversity in the recruitment of human participants. We actively worked to promote sex and gender balance in our author group. The author list of this paper includes contributors from the location and/or community where the research was conducted who participated in the data collection, design, analysis, and/or interpretation of the work.

Changes in the prevalence of intellectual disability among 10-year-old children in Sweden during 2011 through 2021: a total population study

BACKGROUND

Recent studies have suggested an increasing prevalence of intellectual disability diagnoses in some countries. Our aim was to describe the trend in the prevalence of intellectual disability diagnoses in Sweden and explore whether associated sociodemographic and perinatal factors can explain changes in the prevalence.

METHODS

We used a register-based nationwide cohort of residents in Sweden born between 2001 and 2011. We calculated the prevalence of intellectual disability diagnoses by age 10 for each birth cohort and the prevalence ratios in relation to the baseline year 2011, overall and by severity of intellectual disability, and comorbidity of autism and attention-deficit/hyperactivity disorder. The prevalence ratios were stratified and adjusted for associated sociodemographic and perinatal factors.

RESULTS

Among 1,096,800 individuals, 8,577 were diagnosed with intellectual disability by age 10. Among these, 3,949 (46%) and 2,768 (32%) were also diagnosed with autism and attention-deficit/hyperactivity disorder, respectively, and 4% were diagnosed with profound, 8% severe, 20% moderate, 52% mild, and 16% other/unspecific intellectual disability. The recorded age-10 prevalence of intellectual disability diagnoses increased from 0.64% (95% confidence interval 0.59-0.69%) in 2011 to 1.00% (0.94-1.06%) in 2021, corresponding to an annual prevalence ratio of 1.04 (1.04-1.05). The increase was, however, restricted to mild, moderate, and other/unspecific intellectual disability diagnoses, while the trends for profound and severe intellectual disability diagnoses were stable. The increasing trend was perhaps less pronounced among females and children with diagnosed attention-deficit/hyperactivity disorder, but independent of the co-occurrence of autism. The prevalence ratios did not change with stratification or adjustment for other associated demographic and perinatal factors.

CONCLUSION

The recorded prevalence of diagnosed mild and moderate intellectual disability among 10-year-olds in Sweden has increased over the recent decade. This increase could not be explained by changes in associated sociodemographic or perinatal factors, including birth weight, gestational age, and parental age, migration status, and education at the child's birth. The increase instead may be due to changes in diagnostic practices in Sweden over time.

The Impact of Parental Migration on Multidimensional Health of Children in Rural China: The Moderating Effect of Mobile Phone Addiction

Improving physical, mental and cognitive health is a strategic choice to help developing countries cross the middle-income trap. This paper used data from the 2019 China Rural Children Health and Nutrition Survey (n = 826), and used the Ordered Probit (Oprobit), Logit and ordinary least squares (OLS) analytical methods to systematically analyze the implications of parental migration on multidimensional health. The results indicate that parental migration significantly harms the physical and mental health of rural children, and that mobile phone addiction has a significant moderating effect. Moreover, parental migration has a greater impact on the physical health, mental health and cognitive ability of boys and rural children with low family income, while parents with higher nutrition knowledge and education can effectively improve the physical health and cognitive ability of their children. In conclusion, in order to improve the multidimensional health of rural children, the government should strengthen the policy of care and support for children whose parents migrate. Schools and families should pay attention to the supervision of rural children's mobile phone addiction.