The risk of childhood autism among second-generation migrants in Finland: a case-control study

Maternal Eating Disorders, Body Mass Index, and Offspring Psychiatric Diagnoses

Importance

Maternal nutrition is essential in fetal development; thus, disordered eating may influence this process and contribute to the development of offspring psychiatric disorders.

Objective

To investigate the association of maternal eating disorders and prepregnancy body mass index (BMI) with offspring psychiatric diagnoses.

Design, Setting, and Participants

This population-based cohort study used Finnish national registers to assess all live births from January 1, 2004, through December 31, 2014, with follow-up until December 31, 2021. The data analyses were conducted from September 1, 2023, to September 30, 2024.

Exposures

Maternal eating disorder and prepregnancy BMI.

Main Outcomes and Measures

Primary outcomes were 9 neurodevelopmental and psychiatric offspring diagnoses. Cox proportional hazards modeling adjusted for potential risk factors in the development of the outcome disorders was applied in 2 models. Secondary analyses were stratified for adverse birth outcomes (prematurity, small size for gestational age, and low Apgar score) or comorbid offspring eating disorders. Categories of BMI (calculated as weight in kilograms divided by height in meters squared) included underweight (BMI <18.5), normal weight (18.5-24.9), overweight (25.0-29.9), obesity (30.0-34.9), and severe obesity (≥35.0).

Results

The mean (SD) age of 392 098 included mothers was 30.15 (5.38) years, 42 590 mothers (10.86%) were born outside of Finland, 6273 mothers (1.60%) had a history of an eating disorder, 23 114 mothers (5.89%) had prepregnancy underweight, and 208 335 (53.13%) mothers had overweight or obesity. Among 649 956 included offspring, 332 359 (51.14%) were male, and 106 777 (16.43%) had received a neurodevelopmental or psychiatric diagnosis. Maternal eating disorders, prepregnancy underweight, and overweight or obesity were associated with most of the studied mental diagnoses in offspring, even after adjusting for potential covariates. The largest effect sizes were observed for maternal eating disorders not otherwise specified in association with offspring sleep disorders (hazard ratio [HR], 3.34 [95% CI, 2.39-4.67]) and social functioning and tic disorders (HR, 2.79 [95% CI, 2.21-3.52]), while for maternal severe prepregnancy obesity, offspring intellectual disabilities (HR, 2.04 [95% CI, 1.83-2.28]) had the largest effect size. Adverse birth outcomes further increased the risk of offspring having other feeding disturbances of childhood and infancy (eg, HR, 4.53 [95% CI, 2.97-6.89] for maternal eating disorders) and attention-deficit/hyperactivity disorder and conduct disorder (eg, HR, 2.27 [95% CI, 1.74-2.96] for maternal anorexia nervosa).

Conclusions and Relevance

In this population-based cohort study including 392 098 mothers and 649 956 offspring, offspring from mothers with an eating disorder history or prepregnancy BMI outside normal weight were at higher risk of psychiatric disorders. The results differed somewhat between the 2 exposures with regard to which offspring diagnoses had associations, and effect sizes were typically larger for maternal eating disorders vs BMI. These findings suggest a need to consider these 2 exposures clinically to help prevent offspring mental illness.

Intervention in autism based on Early Start Denver Model in a multiethnic immigrant setting-experiences of preschool staff involved in its implementation

Background

Early interventions for young children with autism have been shown to enhance developmental outcomes. However, opportunities for targeted interventions in autism, both in care and preschool, are often lacking, particularly in immigrant communities. The early start denver model (ESDM) stands as one of the most well-established intervention models, including improvement in core developmental domains and reduction of maladaptive behaviours, also delivered in preschool settings. An intervention program based on the ESDM was implemented in collaboration with parents, preschool staff, and health care professionals locally in a multiethnic immigrant and socioeconomically disadvantaged area in Gothenburg, Sweden.

Purpose

The present study aimed to describe a low intensity intervention program based on the ESDM for young children with autism in a multiethnic immigrant setting and capture the experiences of the preschool staff involved in implementing the program.

Method

Fifteen preschool professionals were interviewed through focus group interviews. Data were analyzed using content analysis. The interviews focused on capturing the crucial factors in the intervention program and to get more in-depth information about the intervention program's influence on the children with autism, their parents, the preschool staff, and preschool activities.

Results

Central components of the intervention program were emphasized by the preschool staff. These encompassed contextual prerequisites, such as the preschool staff's participation in intervention program fostered by the local environment and features linked to the ESDM methodology. The preschool staff emphasized that shared objectives and regular network meetings as fundamental components of the model. They also underscored the seamless alignment between the ESDM and the preschool curriculum emphasizing how ESDM strategies could be easily integrated into the preschool's daily routines. The staff's experience indicated that the implementation of ESDM enriched the learning experiences of children with autism and yielded benefits to their parents, fellow peers in the preschool, and the preschool staff.

Conclusions

The intervention program based on the ESDM presents a promising model for young children with autism in a multiethnic immigrant setting. Several critical factors based on the preschool staff's experiences were essential for implementation: contextual prerequisites such as organizational support, close collaboration with healthcare professionals, good competence among preschool staff, and the ESDM itself.

Environmental Influences on Individuals with Autistic Spectrum Disorders with Special Emphasis on Seasonality: An Overview

This paper offers an in-depth exploration of the intricate relationship between environmental factors and autism spectrum disorder (ASD), with a special emphasis on seasonality. It reviews existing research, providing a comprehensive summary of findings and highlighting the multifaceted dimensions of several environmental factors influencing the etiology of ASD. The discussion encompasses various elements, including birth months, maternal health, dietary choices, and vitamin D deficiency, delving into the intricate interplay of seasonality with environmental influences such as viral infections and solar radiation. The present study raises essential questions regarding the timing of environmental influences and the factors contributing to the rising prevalence of ASD. Ultimately, it underscores the need for future epidemiological research to incorporate more extensive investigations of environmental risk factors and employ advanced statistical analyses. This comprehensive overview contributes to a deeper understanding of how environmental factors, particularly seasonality, may be linked to the occurrence of ASD and its increasing prevalence, recognizing the multifaceted and diverse nature of these interactions.

Developmental disorders among Norwegian-born children with immigrant parents

BACKGROUND

Risk of being diagnosed with different developmental disorders is found to vary with immigrant background. Knowledge about such differences in Norway are a starting point for equity in health services quality, and for early identification and prevention. Our objective was to assess the risk of receiving diagnoses of developmental disorders among children born in Norway (2006-2017) to two or one immigrant parent compared to children with two Norwegian-born parents.

METHODS

Information on developmental disorders was from the Norwegian Patient Register (NPR) and information on immigrant background, parental country of origin, parental education, and household income from Statistics Norway. We estimated hazard ratios (HR) with Cox proportional hazard regressions. With children with Norwegian background as reference category, we estimated HRs for immigration background and region of origin. All analyses were adjusted for sex, year of birth, parental education, and household income.

RESULTS

Children with two immigrant parents had a lower risk of receiving any developmental disorder diagnosis [HR 0.80 (95% CI 0.77, 0.82)] than children with Norwegian background, and lower risk of being diagnosed with attention deficit hyperactivity disorder (ADHD) diagnosis [HR 0.24 (95% CI 0.22, 0.27)], learning difficulties diagnosis [HR 0.39 (95% CI 0.33, 0.47)], and behavioral and emotional disorders [HR 0.52 (95% CI 0.49, 0.55)]. Children with immigrant parents had higher hazard than Norwegian background children of autism spectrum disorder (ASD) [HR 2.21 (95% CI 2.04, 2.39)], mental retardation [HR 1.84 (95% CI 1.64, 2.07)], language disorders [HR 1.30 (95% CI 1.20, 1.40)], and unspecified developmental disorders [HR 1.22 (95% CI 1.17, 1.28)]. Children with only one immigrant parent had lower risk of diagnoses than children of two immigrants.

CONCLUSION

Risk of receiving a diagnosis of various developmental disorders varied substantially by immigrant background. Understanding the underlying mechanisms of these differences is warranted to ensure equity in health services and timely intervention.

Birth and Health Outcomes of Children Migrating With Parents: A Systematic Review and Meta-Analysis

Objective

To examine the birth and health outcomes of children migrating with parents internationally and domestically, and to identify whether the healthy migration effect exist in migrant children.

Methods

Five electronic databases were searched for cross-sectional, case-control, or cohort studies published from January 1, 2000 to January 30, 2021and written by English language, reporting the risk of health outcomes of migrant children (e.g., birth outcome, nutrition, physical health, mental health, death, and substance use) We excluded studies in which participants' age more than 18 years, or participants were forced migration due to armed conflict or disasters, or when the comparators were not native-born residents. Pooled odd ratio (OR) was calculated using random-effects models.

Results

Our research identified 10,404 records, of which 98 studies were retrained for analysis. The majority of the included studies (89, 91%) focused on international migration and 9 (9%) on migration within country. Compared with native children, migrant children had increased risks of malnutrition [OR 1.26 (95% CI 1.11-1.44)], poor physical health [OR 1.34 (95% CI 1.11-1.61)], mental disorder [OR 1.24 (95% CI 1.00-1.52)], and death [OR 1.11 (95% CI 1.01-1.21)], while had a lower risk of adverse birth outcome [OR 0.92 (95% CI 0.87-0.97)]. The difference of substance use risk was not found between the two groups.

Conclusion

Migrant children had increased risk of adverse health outcomes. No obvious evidence was observed regarding healthy migration effect among migrant children. Actions are required to address the health inequity among these populations.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/#myprospero, identifier: CRD42021214115.

Migration modulates the prevalence of ASD and ADHD: a systematic review and meta-analysis

BACKGROUND

Migration has been implicated as a risk factor for autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD), but evidence is still limited and inconsistent. We aim to investigate the relationship between migration status and risk of ASD and ADHD.

METHODS

Electronic databases including PubMed, EMBASE, Web of Science, and PsychINFO were searched to identify observational studies on this topic, from inception to February 2021. Random-effects meta-analysis models were used to pool the summary odds ratio (OR) and 95% confidence interval (95% CI), and subgroup analyses were conducted to detect possible discrepancies in associations. Certainty of evidence was assessed as per the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) guidelines.

RESULTS

A total of 13 studies (6,532,546 participants) for ASD, five studies (2,875,070 participants) for ADHD, and six studies (31,158 participants) for hyperactivity were included. Overall, the pooled results indicated that migration was associated with increased risk of ASD (pooled OR: 1.32; 95% CI: 1.07-1.63; P for Z test = 0.010), but no association was found between migration and ADHD (pooled OR: 0.84; 95% CI: 0.53-1.32; P for Z test = 0.452) or hyperactivity (pooled standardized mean difference: -0.073; 95% CIs: - 0.383-0.236; P for Z test = 0.642). Subgroup analyses further demonstrated that maternal migration was ASD risk factor (pooled OR: 1.49; 95% CI: 1.19-1.87), and migrant children were more likely to develop ASD with comorbid intellectual disability (ID) (pooled OR: 1.21, P for interaction = 0.006) than ASD without ID. After standardized the origin of migrants, European migrant children from Americas were at higher risk of ASD and ADHD (pooled OR were 4.13 and 1.26), and increased ASD risk was also observed in African children (pooled OR: 2.72). The GRADE of evidence was very low.

CONCLUSIONS

Maternal migration is a risk factor for ASD, and migrant ASD children are more likely comorbid ID. The role of migration on ADHD remains controversial, more studies are needed to assess the association between migration status and ADHD. Health care practitioners should consider screening and providing extra resources for migrant children.

Environmental exposures associated with elevated risk for autism spectrum disorder may augment the burden of deleterious de novo mutations among probands

Although the full aetiology of autism spectrum disorder (ASD) is unknown, familial and twin studies demonstrate high heritability of 60-90%, indicating a predominant role of genetics in the development of the disorder. The genetic architecture of ASD consists of a complex array of rare and common variants of all classes of genetic variation usually acting additively to augment individual risk. The relative contribution of heredity in ASD persists despite selective pressures against the classic autistic phenotype; a phenomenon thought to be explained, in part, by the incidence of spontaneous (or de novo) mutations. Notably, environmental exposures attributed as salient risk factors for ASD may play a causal role in the emergence of deleterious de novo variations, with several ASD-associated agents having significant mutagenic potential. To explore this hypothesis, this review article assesses published epidemiological data with evidence derived from assays of mutagenicity, both in vivo and in vitro, to determine the likely role such agents may play in augmenting the genetic liability in ASD. Broadly, these exposures were observed to elicit genomic alterations through one or a combination of: (1) direct interaction with genetic material; (2) impaired DNA repair; or (3) oxidative DNA damage. However, the direct contribution of these factors to the ASD phenotype cannot be determined without further analysis. The development of comprehensive prospective birth cohorts in combination with genome sequencing is essential to forming a causal, mechanistic account of de novo mutations in ASD that links exposure, genotypic alterations, and phenotypic consequences.

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

OBJECTIVE

To investigate whether parental migration, parental region of origin, timing of child's birth in relation to maternal migration and parental reason for migration are associated with intellectual disability (ID) with and without autism.

METHODS

We used a register-based cohort of all individuals aged 0-17 years in Stockholm County during 2001-2011. General estimating equation logistic model and additionally sibling comparison were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). The models were adjusted for child's sex and birth year and parental age at child's birth, and additionally for migrant-specific variables in the analyses including only children with migrant parent(s).

RESULTS

Within the eligible sample of 670,098 individuals, 3781 (0.6%) had ID with autism, and 5076 (0.8%) had ID without autism. Compared with children with Swedish-born parents, children with both parents born abroad had an increased risk of ID with autism (OR = 1.6, CI 1.5-1.8) and ID without autism (OR = 1.9, CI 1.7-2.0). Among these children with both parents born abroad, it was protective of ID with autism when the child's birth occurred before and later than four years after maternal migration, which was replicated in the sibling comparison. The associations with both conditions were more pronounced with parental origin in regions comprising low- and middle-income countries and with reasons other than work or study.

CONCLUSIONS

Parental migration is associated with ID regardless of co-occurrence of autism. Our results indicate an association between environmental factors during pregnancy related to migration and offspring ID with autism, although further confirmative studies are needed.

Migration or ethnic minority status and risk of autism spectrum disorders and intellectual disability: systematic review

BACKGROUND

There is an emerging evidence that the migration and the ethnic minority status are associated with the risks of autism spectrum disorder (ASD) and intellectual disability (ID). This systematic review aimed to investigate whether associations are specific to ASD or ID; whether and which migration-related or ethnically determined factors are associated with the risk of ASD and ID; and what mechanisms may explain these risks.

METHODS

A systematic literature search was conducted using Embase, Medline and PsycINFO for studies reporting on the risks of ASD and/or ID among migrants, descendants of migrants and/or ethnic minorities. Risks of any ASD, ASD + ID, ASD - ID and any ID were reviewed in relation to migration and ethnic minority status, with consideration to the study quality. In addition, possible underlying mechanisms suggested in the included studies were summarized.

RESULTS

Thirty-five studies were included. The summarized evidence indicated an increased risk of ASD + ID and a decreased risk of ASD - ID in migrants, descendants of migrants and ethnic minorities. These associations appeared more pronounced among children of migrant mothers, with origin in low-income countries, and among descendants of migrants. Data on ID were scarce. Suggested mechanisms explaining the increased risks of ASD + ID included environmental factors acting in utero and genetic factors (including consanguinity), while ascertainment bias was proposed to account for the lowered risks of diagnosed ASD - ID.

CONCLUSION

Migration-related factors acting in utero and/or associated with origin in low-income countries may be important in the ASD + ID aetiology, although further confirmative studies are needed.

Autism Spectrum and Other Neurodevelopmental Disorders in Children of Immigrants: A Brief Review of Current Evidence and Implications for Clinical Practice

Children of immigrants may have higher neurodevelopmental risks than those of non-immigrant populations. Yet, some evidence suggests that this group may receive late diagnosis, and therefore miss beneficial early interventions. Clinicians may misattribute symptoms of disorders to other social, behavioral or language problems. Likewise, there might be cultural differences in parents' likelihood of perceiving or reporting first developmental concerns to clinicians. Population-based standardized screening may play an important role in addressing ethnic inequalities in the age at diagnosis, although further research focusing on cross-cultural use is necessary. Once children are diagnosed, clinicians may rely on culturally sensitive procedures (translation services, cultural mediators) to increase the accessibility of interventions and improve adherence among immigrant families. In this brief review, we provide an overview about what is currently known about the epidemiology and risk factors of neurodevelopmental disorders, paying special attention to autism spectrum disorder (ASD), in children of immigrants and suggest the necessity of population-based screening and culturally sensitive care.

Explaining Age at Autism Spectrum Diagnosis in Children with Migrant and Non-Migrant Background in Austria

This study explored (i) differences in age at Autism Spectrum Disorder (ASD) diagnosis between children with and without a migrant background in the main diagnostic centre for ASD in Upper Austria (ii) factors related to the age at diagnosis and (iii) whether specific factors differed between the two groups. A retrospective chart analysis included all children who received their first diagnosis before the age of 10 years (n = 211) between 2013 and 2018. Children with a migrant background were diagnosed 13 months earlier than those without (r = 0.278, p < 0.001), and had more severe delays in language, more severe autism, no Asperger’s syndrome, lower parental educational level and more frequent referrals by paediatricians. For the total sample, expressive language delay, severity of restricted and repetitive behaviours, higher nonverbal development, and paediatric referrals explained earlier diagnoses. There was a stronger effect of parental education and weaker effect of language impairment on age at ASD diagnosis in children with a migrant background. In conclusion, no delay in diagnosing ASD in children with a migrant background in a country with universal health care and an established system of paediatric developmental surveillance was found. Awareness of ASD, including Asperger’s syndrome, should be raised among families and healthcare professionals.

Perceptions, Experiences, and Needs of Parents of Culturally and Linguistically Diverse Children with Autism: a Scoping Review

A scoping review of studies carried out in the UK and the USA was conducted to explore the perceptions, experiences, and needs of culturally and linguistically diverse families of children with autism. Overall, 32 articles met the inclusion criteria, 25 studies were conducted in the USA and 7 studies in the UK. Four themes emerged including (a) knowledge and beliefs about autism and their impact on the family; (b) autism and family life; (c) family experiences of accessing services and support, and parents’ needs; and (d) multilanguage. Findings highlighted that family perceptions of autism are influenced by an often-reported lack of knowledge; experiences include social stigma as well as difficulties in having access to services. Needs indicate the development of culturally sensitive interventions, information in multiple languages, and parent–professional collaboration. Implications for research, policy, and practice are included.

Proband and Familial Autoimmune Diseases Are Associated With Proband Diagnosis of Autism Spectrum Disorders

OBJECTIVE

There is evidence that parental autoimmune diseases (ADs) are associated with autism spectrum disorders (ASD) in offspring. The association between offspring ASD and ADs diagnosed in siblings and probands remains less clear. We examined whether proband and familial diagnoses of ADs were associated with increased odds of ASD in probands.

METHOD

The study is based on a nested case-control design that used data from a large national birth cohort (N = 1.2 million) in Finland. There were 4,600 cases of ASD and controls matched 1:4 on date of birth, sex, and residence. Data were accessed from national medical, birth, and central registries.

RESULTS

Probands had a statistically significant increase in odds of ASD when they (adjusted odds ratio [OR] = 1.2), their mother (adjusted OR = 1.1), or their sibling (adjusted OR = 1.2) were diagnosed with an AD. With regard to specific ADs, we found a statistically significant increase in odds of ASD in probands diagnosed with autoimmune thyroiditis (adjusted OR = 2.7). Further analyses considering ADs by body system yielded a statistically significant increase in odds of ASD in probands with ADs associated with the central/peripheral nervous (adjusted OR = 4.8) and skin/mucous membrane (adjusted OR = 1.3) systems. Probands of mothers diagnosed with ear/eye (adjusted OR = 1.6) or respiratory (adjusted OR = 1.4) ADs, or siblings diagnosed with skin/mucous membrane ADs (adjusted OR = 1.3) also had increased odds of ASD.

CONCLUSION

The findings suggest that there may be common pathogenic, developmental mechanisms related to autoimmunity that are associated with the etiology of ASD.

Parental immigration and offspring post-traumatic stress disorder: A nationwide population-based register study

OBJECTIVES

The aim of this study was to investigate the association between parental immigration status and a diagnosis of post-traumatic stress disorder (PTSD) in their offspring.

METHODS

This nested matched case-control study was based on a Finnish national birth cohort for 1987-2010 and cases were diagnosed with PTSD by 2012 from the Care Register for Health Care. We identified 3639 cases and 14,434 controls individually matched for gender, place and date of birth (±30 days). Conditional logistic regression analyses were conducted to examine the association between parental immigration status, parents' region of birth and time since paternal immigration, and PTSD after controlling for confounding factors.

RESULTS

The likelihood of being diagnosed with PTSD was significantly increased among children with an immigrant father (OR 1.8, 95% CI 1.3 - 2.4) than those with two Finnish parents and one immigrant mother. There was no significant association between having an immigrant mother or two immigrant parents and receiving a diagnosis of PTSD. The likelihood of being diagnosed with PTSD was increased if the children's fathers had migrated less than five years before their birth (OR 1.4, 95% CI 1.03 - 1.9) and if their immigrant fathers had been born in North Africa or the Middle East (OR 2.1, 95% CI 1.4 - 3.3).

LIMITATIONS

The sample included a heterogeneous migrant group without information on the reason for migration. The cases were identified from hospital diagnosis that may have only included severe cases.

CONCLUSION

The increased likelihood of a diagnosis of PTSD underlines the need for psychosocial services among second-generation immigrants.

Dioxins as potential risk factors for autism spectrum disorder

Autism spectrum disorder (ASD) has emerged as a major public health concern due to its fast-growing prevalence in recent decades. Environmental factors are thought to contribute substantially to the variance in ASD. Interest in environmental toxins as causes of ASD has arisen due to the high sensitivity of the developing human brain to toxic chemicals, particularly to dioxin and certain dioxin-like compounds (dioxins). As a group of typical persistent organic pollutants, dioxins have been found to exert adverse effects on human brain development. In this paper, we review the evidence for association of exposure to dioxins with neurodevelopmental abnormalities related to ASD based on both human epidemiological and animal studies. It has been documented that exposure to dioxins during critical developmental periods increased risk for ASD. This notion has been demonstrated in different populations exposed to high or background level of dioxins. Furthermore, the effects and mechanisms of action of dioxins relevant to the pathophysiology and pathogenesis of ASD are summarized, describing potential underlying mechanisms linking dioxin exposure with ASD onset. Further studies focusing on effects of prenatal/perinatal exposure to individual dioxin congeners or to mixtures of dioxins on ASD-associated behavioral and neurobiological consequences in animal models, and on the mechanisms of actions of dioxins, are needed in order to better understand how dioxin exposure might contribute to increased risk for ASD.

Finnish-born children of immigrants are more likely to be diagnosed with developmental disorders related to speech and language, academic skills and coordination

AIM

We examined the association between having at least one parent born abroad and being diagnosed with a developmental disorder related to speech and language, academic skills or coordination.

METHODS

This nested case-control study was based on Finnish population records for 1996-2007. Cases from the Finnish Hospital Discharge Register were diagnosed with developmental disorders of speech and language, academic skills and coordination by the end of 2012. We identified 28 192 cases and 106 616 matched controls.

RESULTS

Children were more likely to be diagnosed with developmental disorders if they had an immigrant mother than children with two Finnish-born parents, with an adjusted odds ratio (aOR) of 1.3 and 95% confidence interval (95% CI) of 1.2-1.4, an immigrant father (aOR 1.2, 95% CI 1.1-1.3) or two immigrant parents (aOR 1.5, 95% CI 1.3-1.6). The level of development of the parental country of origin was not associated with receiving a diagnosis.

CONCLUSION

Children of immigrant parents were more likely to be diagnosed with developmental disorders and the association was strongest with regard to speech and language disorders. There were similar adjusted odds ratios for mothers, fathers and both parents. The development level of the country of origin was irrelevant.

Incidence and prevalence of mental disorders among immigrants and native Finns: a register-based study

PURPOSE

Migrants appear to have a higher risk of mental disorders, but findings vary across country settings and migrant groups. We aimed to assess incidence and prevalence of mental disorders among immigrants and Finnish-born controls in a register-based cohort study.

METHODS

A register-based cohort study of 184.806 immigrants and 185.184 Finnish-born controls (1.412.117 person-years) was conducted. Information on mental disorders according to ICD-10 was retrieved from the Hospital Discharge Register, which covers all public health care use.

RESULTS

The incidence of any mental disorder was lower among male (adjusted HR 0.82, 95% CI 0.77-0.87) and female (aHR 0.76, 95% CI 0.72-0.81) immigrants, being lowest among Asian and highest among North African and Middle Eastern immigrants. The incidence of bipolar, depressive and alcohol use disorders was lower among immigrants. Incidence of psychotic disorders was lower among female and not higher among male immigrants, compared with native Finns. Incidence of PTSD was higher among male immigrants (aHR 4.88, 95% CI 3.38-7.05).

CONCLUSIONS

The risk of mental disorders varies significantly across migrant groups and disorders and is generally lower among immigrants than native Finns.

European studies on prevalence and risk of autism spectrum disorders according to immigrant status-a review

Background

Autism spectrum disorders (ASDs), once considered to be rare, are now reaching prevalence estimates of 1% and higher. Studies conducted in North America indicate large racial/ethnic disparities in the diagnosis of ASDs. Others show, that immigrant children have similar prevalence rates of ASDs as native children, although they are diagnosed later compared with native children. In relation to a EU funded network action, Enhancing the Scientific Study of Early Autism, it was considered important to review the literature on this subject.

Method

A comprehensive literature search was undertaken for original articles reporting on prevalence and risk for ASD in Europe among immigrants and ethnic minorities and data across studies were compared.

Results

Seventeen studies conducted in Europe concerning immigrants and ethnic minorities were found. Fifteen studies suggest a higher prevalence rate of ASDs among children of immigrants in comparison to native children (RR = 1.02-1.74; OR = 0.6-10.5). One study revealed higher prevalence of autism (OR = 2.2; 95% CI 1.6-3.1) and lower prevalence of Asperger syndrome in immigrants (OR = 0.6; 95% CI 0.3-0.97). One study showed a lower prevalence of Asperger syndrome in immigrants (aOR = 0.1, 95% CI 0.01-0.5). The majority of those analyses involved immigrants from outside Europe, e.g. from Africa and South America.

Conclusion

After analysing the results of studies conducted in Europe, it is unclear if higher prevalence estimates of ASDs among immigrants in this region reflect true differences, especially considering many potential confounding factors, e.g. genetic, biological, environmental and cultural. Considering the number of people migrating within Europe there is a substantial need to study further the prevalence of ASDs in immigrant groups.

What do register-based studies tell us about migrant mental health? A scoping review

BACKGROUND

Previous studies investigating the mental health of migrants have shown mixed results. The increased availability of register data has led to a growing number of register-based studies in this research area. This is the first scoping review on the use of registry and record-linkage data to examine the mental health of migrant populations. The aim of this scoping review is to investigate the topics covered and to assess the results yielded from these studies.

METHODS

We used a scoping review methodology to search MedLine, PubMed, PsychINFO, Web of Science, and SCOPUS for all register-based studies on the mental health of migrants. Two reviewers screened all papers, independently, using iteratively applied inclusion and exclusion criteria. Using gradually broadening inclusion and exclusion criteria for maximum "scope," newly published criteria developed to appraise the methodological quality of record-linkage studies were applied to eligible papers and data were extracted in a charting exercise.

RESULTS

A total of 1309 papers were screened and appraised, 51 of which met the eligibility and quality criteria and were included in the review. This review identified four major domains of register-based research within the topic of migrant mental health: rates and risks of psychiatric disorders, rates and risks of suicide mortality, the use of psychotropic drugs, and health service utilisation and mental health-related hospitalisation rates. We found that whilst migrants can be at an increased risk of developing psychotic disorders and suicide mortality, they are less likely to use psychotropic medication and mental health-related services.

CONCLUSIONS

This review systematically charts the register-based studies on migrants' mental health for the first time. It shows the main topics and gaps in knowledge in this research domain, discusses the disadvantages of register-based studies, and suggests new directions for forthcoming studies.

"It was like walking without knowing where I was going": A Qualitative Study of Autism in a UK Somali Migrant Community

Increasing recognition of autism in Somali migrant communities means that appropriate support services are needed. Attitudes to autism and barriers related to help-seeking in these communities are poorly understood. We aimed to assess what families affected by autism need, and how health, education and social care services can support them. In partnership with the local Somali community the research team conducted 15 in-depth interviews with parents affected by autism. Two themes are reported; 'Perceptions of Autism' and 'Navigating the System'. Our research shows the importance of understanding cultural views of autism and the need to raise awareness, reduce stigma and provide support to encourage families not to delay seeking help for their children.

Association between immigrant background and ADHD: a nationwide population-based case-control study

BACKGROUND

Information about psychiatric disorders among those with immigrant parents is important for early detection and service development. The aim of this study is to examine the association between parental immigration and the diagnosis of attention-deficit hyperactivity disorder (ADHD) in offspring in Finland.

METHODS

This matched case-control study was based on a national birth cohort. The sample included all singletons who were born in Finland in 1991-2005 and diagnosed with ADHD by the year 2011 (n = 10,409) and their matched controls (n = 39,124). Nationwide registers were used to identify participants and to gather information on the parents' country of birth and native language. Conditional logistic regression analyses were conducted using maternal and paternal migration status and region of birth as well as time since maternal migration as exposure factors.

RESULTS

The likelihood of being diagnosed with ADHD was significantly increased among children of two immigrant parents [adjusted odds ratio (aOR) 4.7, 95% CI 3.4-6.6] and children of an immigrant father (aOR 1.9, 95% CI 1.6-2.2). The likelihood of receiving an ADHD diagnosis was equal among children whose mother was a recent immigrant when she gave birth and those whose mother had stayed in Finland at least for a year before birth. The association between parental migration and ADHD diagnosis was strongest among fathers born in sub-Saharan Africa or Latin America and among mothers born in sub-Saharan Africa or North Africa and Middle East. Children, whose parents were born in countries with low Human Development Index (HDI), were more often diagnosed with ADHD.

CONCLUSIONS

The increased likelihood of ADHD diagnosis among children of immigrants indicates increased exposure to environmental risk factors, differences in the use of health services, or challenges in diagnosing immigrants' children.

Learning Problems in Children of Refugee Background: A Systematic Review

CONTEXT

Learning problems are common, affecting up to 1 in 10 children. Refugee children may have cumulative risk for educational disadvantage, but there is limited information on learning in this population.

OBJECTIVE

To review the evidence on educational outcomes and learning problems in refugee children and to describe their major risk and resource factors.

DATA SOURCES

Medline, Embase, PubMed, Cumulative Index to Nursing and Allied Health Literature, PsycINFO, and Education Resources Information Center.

STUDY SELECTION

English-language articles addressing the prevalence and determinants of learning problems in refugee children.

DATA EXTRACTION

Data were extracted and analyzed according to Arksey and O'Malley's descriptive analytical method for scoping studies.

RESULTS

Thirty-four studies were included. Refugee youth had similar secondary school outcomes to their native-born peers; there were no data on preschool or primary school outcomes. There were limited prevalence data on learning problems, with single studies informing most estimates and no studies examining specific language disorders or autism spectrum disorders. Major risk factors for learning problems included parental misunderstandings about educational styles and expectations, teacher stereotyping and low expectations, bullying and racial discrimination, premigration and postmigration trauma, and forced detention. Major resource factors for success included high academic and life ambition, "gift-and-sacrifice" motivational narratives, parental involvement in education, family cohesion and supportive home environment, accurate educational assessment and grade placement, teacher understanding of linguistic and cultural heritage, culturally appropriate school transition, supportive peer relationships, and successful acculturation.

LIMITATIONS

Studies are not generalizable to other cohorts.

CONCLUSIONS

This review provides a summary of published prevalence estimates for learning problems in resettled refugee children, highlights key risk and resource factors, and identifies gaps in research.

Changes in prevalence of autism spectrum disorders in 2001-2011: findings from the Stockholm youth cohort

In a record-linkage study in Stockholm, Sweden, the year 2011 prevalence of diagnosed autism spectrum disorders (ASD) was found to be 0.40, 1.74, 2.46, and 1.76% among 0-5, 6-12, 13-17, and 18-27 year olds, respectively. The corresponding proportion of cases with a recorded diagnosis of intellectual disability was 17.4, 22.1, 26.1 and 29.4%. Between 2001 and 2011, ASD prevalence increased almost 3.5 fold among children aged 2-17 years. The increase was mainly accounted for by an eightfold increase of ASD without intellectual disability (from 0.14 to 1.10 %), while the prevalence of ASD with intellectual disability increased only slightly (from 0.28 to 0.34%). The increase in ASD prevalence is likely contributed to by extrinsic factors such as increased awareness and diagnostics.

Parental migration and Asperger's syndrome

Parental immigration has been suggested as a possible risk factor for autism spectrum disorders (ASD), but findings have been inconsistent. Very few studies have focused specifically on Asperger's syndrome. The aim of this study was to examine the association between maternal and paternal immigration and the diagnosis of Asperger's syndrome in offspring. The study was a nested case-control study based on a national birth cohort in Finland. Children born in 1987-2005 and diagnosed with Asperger's syndrome by the year 2007 were identified from the Finnish Hospital Discharge Register (N = 1,783). Four matched controls for each case were selected from the Finnish Medical Birth Register (N = 7,106). Information on maternal and paternal country of birth and mother tongue was collected from the Finnish Central Population Register. The study showed that children whose parents are both immigrants have a significantly lower likelihood of being diagnosed with Asperger's syndrome than those with two Finnish parents [adjusted odds ratio (aOR) 0.2, 95 % confidence interval (CI) 0.1-0.4]. No significant associations were found between having only one immigrant parent and the diagnosis of Asperger's syndrome. A regional analysis showed a significantly decreased likelihood of the diagnosis of Asperger's syndrome in children whose mother (aOR 0.1, 95 % CI 0.01-0.5) or father (aOR 0.2, 95 % CI 0.05-0.5) was born in Sub-Saharan Africa. The findings may help in identifying risk factors for different ASD subtypes. On the other hand, they might reflect service use of immigrant families in Finland.

Autism spectrum disorder and low vitamin D at birth: a sibling control study

BACKGROUND

Insufficient vitamin D activity has attracted increasing interest as a possible underlying risk factor in disorders of the central nervous system, including autism.

METHODS

In this study, 25-hydroxyvitamin D (25(OH)D) was analysed in 58 Sweden-born sibling pairs, in which one child had autism spectrum disorder (ASD) and the other did not. The study group consisted of two representative samples; 47 Gothenburg sibling pairs with mixed ethnicities and 11 Stockholm sibling pairs with Somali background. 25(OH)D levels were analysed in the stored dried blood spots taken in the neonatal period for metabolic screening.

RESULTS

The collapsed group of children with ASD had significantly lower vitamin D levels (M = 24.0 nM, SD = 19.6) as compared with their siblings (M = 31.9 nM, SD = 27.7), according to a paired samples t-test (P = 0.013). The difference was - most likely - not only accounted for by a difference in season of birth between ASD and non-ASD siblings since the mean 25(OH)D levels differed with similar effect size between the sibling pairs born during winter and summer, respectively. All children with African/Middle East background, both the children with ASD and their non-ASD siblings, had vitamin D deficiency.

CONCLUSIONS

The findings suggest that low prenatal vitamin D may act as a risk factor for ASD, however, there is a need for replication with larger samples. Future research should study whether or not adequate supplementation of vitamin D to pregnant women might lower the risk for ASD in the offspring.