Psychotherapy use among migrants: a register-based longitudinal study.

BACKGROUND: Migrants use less mental health services compared with non-migrant populations, but there is very little information on the use of long-term psychotherapy among migrants. Finnish register data allow for studying the whole migrant population in Finland and collecting data on all publicly supported rehabilitative psychotherapy. METHODS: This study is based on a sample of migrants (n=185 605) and Finnish-born controls (n=185 605). Participants who had received reimbursements for rehabilitative psychotherapy during 2007-2020 were identified from a register maintained by the Social Insurance Institution of Finland. Cox regression analysis was used to study the effect of migrant status on the time until the start of therapy. Multinomial logistic regression was used to study the association between migrant status and the number of psychotherapy sessions. RESULTS: Finnish-born participants received psychotherapy more often (n=7258) than migrants (n=1516). The adjusted HR for initiating psychotherapy among migrants compared with Finnish-born individuals was 0.27 (95% CI 0.25 to 0.28). Migrants from sub-Saharan Africa and Asia and recently arrived migrants were least likely to receive psychotherapy. Migrants were more likely to receive short treatment periods than Finnish-born controls. CONCLUSION: Lower use of rehabilitative psychotherapy among migrant population in Finland is not likely to reflect lower need for treatment. More efforts are needed to promote equal access to psychotherapy.

Fostering trust and understanding in social and healthcare services with migrant-origin parents: qualitative focus-group interviews of foreign-born mothers living in Finland.

Migrant-origin families may have a pronounced need for psychosocial support and healthcare services, but they face barriers in using services. To ensure the timely use of services, it is important that families understand how service systems work and trust care providers. Thirty-two migrant-origin mothers living in Finland participated in five focus-group interviews and shared their wishes for social and healthcare professionals on how trust and understanding can be increased. The data were analyzed with Qualitative Content Analysis. We identified six main themes related to the use of services and professionals' behavior. These were the need for professionals to justify and explain questions, to meet each family as individuals, the importance of non-verbal communication, the need to talk about racism and discrimination, the importance of cultural sensitivity in services, and a discussion of positive aspects of life after migration and children`s strengths. To foster trust and mutual understanding in social and healthcare services, professionals should be aware of potential cultural differences in family life, while avoiding pre-conceived ideas. Misunderstandings can rise from language barriers and unclear or intimidating questions. It is important that professionals explain what they do and justify why they might inquire about a family's personal matters. Working with interpreters is necessary when professionals and parents do not share a common fluent language. Professionals should also pay attention to their non-verbal communication and to being friendly. Finally, it is important to show interest in families' experienced hardships such as racism as well as their strengths.

Continuity of antipsychotic medication use among migrant and Finnish-born populations with a psychotic disorder: a register-based study.

BACKGROUND: Higher incidence of psychotic disorders and underuse of mental health services have been reported among many migrant populations. This study examines the initiation and continuity of antipsychotic treatment among migrants and non-migrants with a non-affective psychosis during a new treatment episode. METHODS: This study is based on a nationwide sample of migrants and Finnish-born controls. Participants who were diagnosed with a psychotic disorder in 2011-2014 were identified from the Care Register for Health Care (n = 1693). Information on purchases of antipsychotic drugs in 2011-2015 was collected from the National Prescription Register. The duration of antipsychotic treatment since diagnosis was estimated using the PRE2DUP model. Cox regression analysis was used to study factors that are associated with discontinuing the use of medication. RESULTS: There were fewer initiators of antipsychotic treatment after being diagnosed with psychosis among migrants (68.1%) than among Finnish-born patients (73.6%). After controlling for sociodemographic background and factors related to the type of disorder and treatment, migrants were more likely to discontinue medication (adjusted hazard ratio 1.28, 95% confidence interval 1.08-1.52). The risk of discontinuation was highest among migrants from North Africa and the Middle East and Sub-Saharan Africa and among recent migrants. Non-use of antipsychotic treatment before being diagnosed with psychosis, involuntary hospitalization and diagnosis other than schizophrenia were associated with earlier discontinuation both among migrants and non-migrants. CONCLUSIONS: Migrants with a psychotic disorder are less likely to continue antipsychotic treatment than non-migrants. The needs of migrant patients have to be addressed to improve adherence.

Use of benzodiazepine and related drugs in migrants and Finnish-born persons: a nationwide register-based study.

AIMS: Benzodiazepines and related drugs (BZDR) are often used longer than generally recommended. The aim is to study patterns of use among migrant and Finnish-born users of BZDR, and to identify factors that are associated with long-term use and BZDR polytherapy. METHODS: This register-based study includes a nationwide sample of migrants (n=8729) and their Finnish-born controls (n=11 388) who had purchased BZDR in 2011-2014, but not in 2009-2010. Information on drug purchases was obtained from the National Prescription Register and the duration of drug use was estimated using PRE2DUP method. The main outcomes were long-term use of BZDR, polytherapy and time until discontinuation of BZDR use. Sociodemographic variables and information on preceding psychiatric diagnoses were included as covariates. Logistic and Cox regression analyses were the statistical methods used. RESULTS: Only migrants from Sub-Saharan Africa were more likely to discontinue the medication once initiated than Finnish-born users. Migrants were significantly less likely to be long-term users (adjusted odds ratio 0.79, 95% CI 0.70-0.89) or polytherapy users (aOR 0.90, 95% CI 0.84-0.97) of BZDR compared with Finnish-born participants. CONCLUSIONS: Migrants had less long-term and concomitant use of several BZDR than Finnish-born participants. The pattern of use is more optimal among migrants, but it may also reflect poorer access to mental health treatment.

Antidepressant use among immigrants with depressive disorder living in Finland: A register-based study.

BACKGROUND: The aim of this study was to examine differences in the initiation and discontinuation of antidepressants between immigrants and the Finnish-born population diagnosed with depression in specialized health care. METHODS: The study utilized register-based data, which includes all immigrants living in Finland at the end of 2010 and matched Finnish-born controls. For this study, we selected individuals who had received a diagnosis of depression during 2011-2014 (immigrants n = 2244, Finnish-born n = 2773). Their antidepressant use was studied for a one-year period from initiation. A logistic regression was used to predict initiation and a Cox regression was used to predict discontinuation. RESULTS: Immigrants were more likely to initiate the use of antidepressants than the Finnish-born controls (adjusted OR = 1.25, 95% CI = 1.07-1.46), but they also discontinued the medication earlier than the Finnish-born controls (adjusted HR = 1.48, 95% CI = 1.31-1.68). Immigrants from Sub Saharan Africa, the Middle East and Northern Africa were most likely to discontinue antidepressants earlier. More severe depression, a longer length of residence in Finland and more intensive psychiatric treatment were associated with decreased risk of discontinuation. LIMITATIONS: The registers do not provide information on the perceived reasons for the discontinuation. CONCLUSIONS: Immigrants with depression initiate antidepressants more often than the Finnish-born population, but they also discontinue them earlier. Early discontinuation may be a sign of insufficient treatment suggesting that there could be a need for improvement in mental health care for immigrants in Finland.

Post-traumatic stress disorder among immigrants living in Finland: Comorbidity and mental health service use.

The aim of this study was to compare differences in comorbidity between immigrants and Finnish-born controls, and to examine the treatment received by immigrants with PTSD. Our original data included all the immigrants living in Finland by the end of 2010 and matched controls. For this study, we selected individuals who had received a diagnosis of PTSD during 2010-2015 (immigrants: n = 754, Finnish-born controls: n = 311). We compared the frequency of different comorbid conditions between immigrants and natives. Multinomial logistic regression was used to predict categorized treatment intensity with the region of origin and length of residence among the immigrants. Psychiatric comorbidity was much more extensive among the Finnish-born controls than among immigrants. Immigrants from Africa and the Middle East more often received treatment of low intensity compared with immigrants from Western countries. The length of residence was associated with more frequent treatment. The important differences in comorbidity and background characteristics between immigrants and natives should be taken into account in planning treatment guidelines for PTSD. The disparities in treatment intensity across different immigrant groups indicate a need to improve the services for immigrants with PTSD.

Depression and anxiety disorders among immigrants living in Finland: Comorbidity and mental health service use.

BACKGROUND: The aims of this study were to (1) compare differences in psychiatric comorbidity of depression and anxiety disorders between immigrants and native Finns and to (2) compare differences in the intensity of psychiatric care received by different immigrant groups and Finnish-born controls with depression and/or anxiety disorders. METHODS: The study uses registered-based data, which includes all immigrants living in Finland at the end of 2010 and matched Finnish-born controls. For this study, we selected individuals who had received a diagnosis of depression and/or an anxiety disorder during the follow-up (2011-2015) (immigrants n = 6542, Finnish-born controls n = 9281). We compared differences in comorbidity between the immigrants and the Finnish-born controls using chi-squared tests. Multinomial logistic regression was used to predict psychiatric treatment intensity by immigrant status, region of origin, and other background factors. RESULTS: In both diagnosis groups, Finnish-born participants exhibited greater comorbidity of other psychiatric disorders. Immigrants more often received lower intensity treatment and less often higher intensity treatment. These differences were most striking among those from Eastern Europe, the Middle East, and Africa. LIMITATIONS: We did not have the information on the perceived need for the services, which limits us from drawing further conclusions about the mechanisms behind the observed patterns. CONCLUSIONS: Immigrants in Finland receive less intensive treatment for depression and anxiety disorders compared to the Finnish-born population. Since lower symptom levels can unlikely alone explain these differences, they could reflect a need for improvement in the psychiatric services for immigrants.

Purchases of psychotropic drugs among the migrant population in Finland: a nationwide register-based cohort study.

BACKGROUND: Migrant populations may have different mental health service needs when compared with native populations. One indicator of service use is the use of psychotropic medication. The aim of this study was to compare the purchases of psychotropic drugs among different migrant populations with the native population in Finland. METHODS: Foreign-born participants (n = 184 805) and their Finnish-born controls (n = 185 183) were identified from the Finnish Central Population Register. Information on their purchases of psychotropic drugs in 2011-15 was collected from the National Prescription Register. A washout period of 2009-10 was used to define incident purchases. Cox regression analysis was the statistical method used. RESULTS: At least one incident purchase of a psychotropic drug was identified for 11.1% of migrant women, 11.4% of Finnish-born women, 8.7% of migrant men and 9.8% of Finnish-born men. When controlled for age, sex, marital status, socioeconomic status and social assistance, migrants were less likely to purchase psychotropic drugs (adjusted hazard ratio 0.96, 95% confidence interval 0.93-0.98), but there was variation between different drug categories. Recent migrants and migrants from Asia and Sub-Saharan Africa were least likely to purchase drugs. Migrants from Nordic countries and other Western countries most closely resembled the Finnish-born controls. CONCLUSIONS: Recent migrants in Finland appear to use fewer psychotropic drugs than native Finns. It is important to analyze the reasons for this pattern, as they may indicate delays in access to care or benefits. The heterogeneity of migrant populations must also be considered when developing services to better address their needs.

Immigrants' mental health service use compared to that of native Finns: a register study.

PURPOSE: Many aspects related to migration might predispose immigrants to mental health problems. Yet immigrants have been shown to underuse mental health services. The aim of this study was to compare the intensity of psychiatric care, as an indicator of treatment adequacy, between natives and immigrants living in Finland. METHODS: We used nationwide register data that included all the immigrants living in Finland at the end of 2010 (n = 185,605) and their matched controls. Only those who had used mental health services were included in the analyses (n = 14,285). We used multinomial logistic regression to predict the categorized treatment intensity by immigrant status, region and country of origin, length of residence, and other background variables. RESULTS: Immigrants used mental health services less than Finnish controls and with lower intensity. The length of residence in Finland increased the probability of higher treatment intensity. Immigrants from Eastern Europe, sub-Saharan Africa, the Middle East, and Northern Africa were at the highest risk of receiving low-intensity treatment. CONCLUSIONS: Some immigrant groups seem to persistently receive less psychiatric treatment than Finnish-born controls. Identification of these groups is important and future research is needed to determine the mechanisms behind these patterns.

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.

Social risk factors for speech, scholastic and coordination disorders: a nationwide register-based study.

BACKGROUND: Broadly defined learning and coordination disorders (LCDs) are common in the population and have previously been associated with familial social risk factors and male sex. However, comprehensive nationwide studies of these risk factors in LCD subgroups are lacking. Our objective was to assess different LCDs in relation to sex and maternal education, marital status and socioeconomic status based on occupation. METHODS: We conducted a nationwide register-based study. The following diagnoses were identified from the Finnish Hospital Discharge Register (FHDR) according to the ICD-10 (n = 28,192): speech disorders (F80), scholastic disorders (F81), motor and coordination disorders (F82) and mixed developmental disorder (F83). To study cumulative incidence and male: female ratios of service use of LCDs, we used a cohort design among all Finnish children born singleton 1996-2007 (n = 690,654); to study social risk factors, we used a nested case-control design with extensive register data on both cases and matched controls (n = 106,616). RESULTS: The cumulative incidence was 4.7% for any LCD by age 15 and the changes in cumulative incidence over time were minor. The male: female ratios were 2.2-3.0 across LCD subgroups. Learning and coordination disorders were more common in households with lower maternal education, socioeconomic status based on occupation and among children with single mothers at the time of birth; the odds ratios (OR) for any LCD were 1.2-1.9 across risk factors. The odds for LCD diagnosis increased linearly with the number of social risk factors, except for coordination disorder. The effect size of three risk factors was highest in the group with mixed or multiple LCDs; OR 3.76 (95% CI 3.31-4.28). CONCLUSIONS: Multiple social risk factors increase the odds for multiple, more comprehensive learning difficulties. The findings have implications for service planning, as early identification and interventions of learning and coordination disorders might reduce related long-term social adversities.

Use of health services among international migrant children - a systematic review.

BACKGROUND: Migrant children have specific health needs, and may face difficulties in accessing health care, but not enough is known about their health service use. This study aims to describe patterns of use of health services of international migrant children and differences to respective native populations. METHODS: Electronic databases PubMed and Web of Science, references of identified publications, and websites of relevant international agencies were searched. We included observational studies published between 2006 and 2016 that reported use of formal health services by migrant children (0-18 years), including first and second generation migrants. Data on study characteristics, study theme, main outcome and study quality were extracted. RESULTS: One hundred seven full texts were included in the review. Of the studies that reported comparable outcomes, half (50%) indicated less use of healthcare by migrants compared with non-migrants; 25% reported no difference, 18% reported greater use, and 7% did not report this outcome. There was variation by theme, so that the proportion of conclusions "less use" was most common in the categories "general access to care", "primary care" and "oral health", whereas in the use of emergency rooms or hospitalisations, the most common conclusion was "greater use". CONCLUSIONS: Migrant children appear to use different types of healthcare services less than native populations, with the exception of emergency and hospital services. SYSTEMATIC REVIEW REGISTRATION: PROSPERO systematic review registration number: CRD42016039876 .

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.

Mortality and causes of death among the migrant population of Finland in 2011-13.

Background: Lower mortality among migrants than in the general population has been found in many, but not in all, previous studies. The mortality of migrants has not been studied in Finland, which has a relatively small and recent migrant population. Methods: People who were born abroad and whose mother tongue is not Finnish were identified from the Finnish Central Population Register (n = 185 605). A Finnish-born control matched by age, sex and place of residence was identified for each case (n = 185 605). Information about deaths was collected from the Finnish Causes of Death Register. Cox proportional hazards model was used for assessing the association between migrant status and death in 2011­13. Results: The mortality risk was found to be significantly lower for migrants than for Finnish controls (adjusted hazard ratio 0.77, 95% CI 0.72­0.84), both for migrant men (aHR 0.80, 95% CI 0.73­0.89) and women (aHR 0.78, 95% CI 0.70­0.88). The difference was statistically significant only among people who were not married and among people who were not in employment. There was variation by country of birth, but no migrant group had higher mortality than Finnish controls. No differences in mortality were found by duration of residence in Finland. The higher mortality of Finnish controls was largely explained by alcohol-related conditions and external causes of death. Conclusions: The mortality risk of migrants is lower than of people who were born in Finland. Possible explanations include selection and differences in substance use and other health behaviour.

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.

Parental age and the risk of attention-deficit/hyperactivity disorder: a nationwide, population-based cohort study.

OBJECTIVE: An increasing number of studies has shown an association between parental age and psychiatric disorders. However, there are inconsistent results regarding whether age at parenthood is associated with attention-deficit/hyperactivity disorder (ADHD). The aim of this study is to examine whether low or advanced parental age is associated with ADHD. METHOD: In this nested case-control study, we identified 10,409 individuals with ADHD born in Finland during 1991 to 2005 and diagnosed with ADHD between 1995 and 2011, along with 39,125 controls matched on sex, date, and place of birth, from nationwide population-based registers. Conditional logistic regression was used to examine the association between parental age and ADHD in offspring, adjusting for potential confounding due to parental psychiatric history, maternal socioeconomic status, marital status, maternal smoking during pregnancy, number of previous births, and birth weight for gestational age. RESULTS: Fathers younger than 20 years had a 1.5-fold (odds ratio [OR] = 1.55, 95% CI = 1.11-2.18, p = .01) increased risk of having offspring with ADHD as compared to fathers aged 25 to 29 years. Mothers of the same age group had a 1.4-fold (OR = 1.41, 95% CI = 1.15-1.72, p =.0009) increased risk. Advanced maternal age was inversely associated with ADHD (OR = 0.79, 95% CI = 0.64-0.97, p = .02). CONCLUSION: ADHD was associated with young fathers or mothers at the time of birth. Health professionals working with young parents should be aware of the increased risk of ADHD in offspring. This will improve early detection; however, for the development of preventive measures and appropriate interventions, more information on the developmental pathways is needed.

Maternal socio-economic status based on occupation and autism spectrum disorders: a national case-control study.

BACKGROUND: The association between parental socio-economic status (SES) and autism spectrum disorders (ASD) has been studied in several countries, but the results have been contradictory. AIMS: The aim of this study was to examine the association between maternal SES and subtypes of ASD in Finland. METHODS: A national case-control study was conducted. Children born in 1991-2005 and diagnosed with ASD by the year 2007 were identified from the Finnish Hospital Discharge Register (FHDR). Their matched controls were selected from the Finnish Medical Birth Register (FMBR). There were 3468 cases and 13,868 controls. The information on maternal SES was collected from the FMBR and categorized into upper white-collar workers (referent), lower white-collar workers, blue-collar workers and "others", consisting of students, housewives and other groups with unknown SES. The statistical test used was conditional logistic regression. RESULTS: The likelihood of ASD was increased among offspring of mothers who belong to the group "others" (adjusted OR = 1.2, 95% CI 1.009-1.3). The likelihood of Asperger's syndrome was decreased among offspring of lower white-collar workers (adjusted OR = 0.8, 95% CI 0.6-0.9) and blue-collar workers (adjusted OR = 0.6, 95% CI 0.5-0.7). The likelihood of pervasive developmental disorder not otherwise specified (PDD-NOS) was increased among offspring of blue-collar workers (adjusted OR = 1.5, 1.2-1.9) and "others" (adjusted OR = 1.3, 1.1-1.7). No association was found between maternal SES and childhood autism. CONCLUSIONS: The association between maternal SES and ASD differs by ASD subtype. Socio-economic groups might differ from each other by risk factors for ASD subtypes or by their service use.

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.