Sex differences across developmental domains among children with a familial risk of severe mental disorders

BACKGROUND

Sex differences in brain structure and neurodevelopment occur in non-clinical populations. We investigated whether sex had a similar effect on developmental domains amongst boys and girls with a familial risk of schizophrenia (FHR-SZ), bipolar disorder (FHR-BP), and controls.

METHODS

Through Danish registries, we identified 522 7-year-old children (242 girls) with FHR-SZ, FHR-BP, and controls. We assessed their performance within the domains of neurocognition, motor function, language, social cognition, social behavior, psychopathology, and home environment.

RESULTS

FHR-SZ boys compared with FHR-SZ girls had a higher proportion of disruptive behavior and attention-deficit hyperactivity disorder (ADHD) and exhibited lower performance in manual dexterity, balance, and emotion recognition. No sex differences were found between boys and girls within FHR-BP group. Compared with controls, both FHR-SZ boys and FHR-SZ girls showed impaired processing speed and working memory, had lower levels of global functioning, and were more likely to live in an inadequate home environment. Compared with control boys, FHR-SZ boys showed impaired manual dexterity, social behavior, and social responsiveness, and had a higher proportion of ADHD and disruptive behavior disorder diagnoses. Stress and adjustment disorders were more common in FHR-BP boys compared with control boys. We found no differences between FHR-BP girls and control girls.

CONCLUSIONS

Impairment within neurodevelopmental domains associated within FHR-SZ boys v. FHR-SZ girls was most evident among boys, whereas no sex differences were found within the FHR-BP group (FHR-BP boys v. FHR-BP girls). FHR-SZ boys exhibited the highest proportion of early developmental impairments.

A study protocol for the randomized controlled trial SAFIR FAMILY TALK: a selective primary preventive intervention vs. service as usual for children of parents with mental illness

BACKGROUND

Children of parents with mental illness have an increased risk of developing mental illness themselves throughout their lifespan. This is due to genetic factors but also environmental disadvantages during childhood associated with parental mental illness. Selective primary preventive interventions for the children are recommended to mitigate risk factors and strengthen protective factors, but large-scale, longitudinal studies are needed. This study aims to investigate the effect of the Family Talk Preventive Intervention in a cohort of children and their parents with mental illness.

METHODS

The study is a randomized controlled trial with 286 planned families with at least one parent with any mental illness and at least one child aged 7 to 17 years. It will be carried out in the mental healthcare system in the Capital Region of Denmark. Families will be referred from hospitals and municipalities. The children and parents will be assessed at baseline and then randomized and allocated to either the Family Talk Preventive Intervention or service as usual. The intervention group will be assigned to Family Talk Preventive Intervention, a manualized programme consisting of ~ seven sessions for the family, including psychoeducation about parental mental illness and resilience in children, stimulating dialogue between family members and creating a common family narrative. The study period for both groups will be 12 months. Follow-up assessments will be conducted after 4 months and 12 months. The primary outcomes are the children's level of functioning, parental sense of competence and family functioning.

DISCUSSION

Given the prevalence of transgenerational transmission of mental illness, a systematic approach to prevention is needed in the mental healthcare setting. This study provides valuable knowledge on the Family Talk Preventive Intervention with a large sample size, inclusion of any parental mental illness and examination of the primary outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05615324. Registered on 26 October 2022. Retrospectively registered.

Home environment of 11-year-old children born to parents with schizophrenia or bipolar disorder - a controlled, 4-year follow-up study: The Danish High Risk and Resilience Study - VIA 11

BACKGROUND

The home environment has a major impact on child development. Parental severe mental illness can pose a challenge to the home environment of a child. We aimed to examine the home environment of children of parents with schizophrenia or bipolar disorder and controls longitudinally through at-home assessments.

METHODS

Assessments were conducted within The Danish High Risk and Resilience Study, a nationwide multi-center cohort study of children of parents with schizophrenia or bipolar disorder and population-based controls. The level of at-home stimulation and support was measured at age 7 (N = 508 children) and age 11 (N = 430 children) with the semi-structured HOME Inventory. Results from the 11-year follow-up study were analyzed and compared with 7-year baseline results to examine change across groups.

RESULTS

At age 11, children of parents with schizophrenia and bipolar disorder had lower levels of stimulation and support than controls (mean (s.d.) = 46.16 (5.56), 46.87 (5.34) and 49.25 (4.37) respectively, p < 0.001). A higher proportion of children with parental schizophrenia or bipolar disorder lived in inadequate home environments at age 11, compared with controls (N (%) = 24 (15.0), 12 (12.2) and 6 (3.5) respectively, p < 0.003). The changes in home environment scores did not differ across groups from age 7 to age 11.

CONCLUSIONS

Assessed longitudinally from the children's age of 7 to 11, children of parents with schizophrenia or bipolar disorder had lower levels of stimulation and support in their homes than controls. Integrated support which can target practical, economic, social and health issues to improve the home environment is indicated.

Affective lability in parents with schizophrenia or bipolar disorder and their co-parents - The Danish High Risk and Resilience Study VIA 7

In bipolar disorder, dysregulation of affect is a core feature while knowledge on affective lability in schizophrenia is sparse. Research on affective lability in partners to individuals with schizophrenia or bipolar disorder is also lacking. The objective of this study was to investigate affective lability in parents with schizophrenia or bipolar disorder, and their co-parents without these disorders. The Danish High Risk and Resilience Study - VIA 7 is a population-based cohort study. This study focuses on parents diagnosed with schizophrenia (n = 148), their co-parents (n = 157), parents with bipolar disorder (n = 98), their co-parents (n = 89) and control parents (n = 359). The Affective Lability Scale - short form (ALS-SF) was used to measure affective lability. We found significantly higher levels of affective lability in parents with schizophrenia and bipolar disorder compared with controls, but no significant differences between bipolar disorder and schizophrenia. Co-parents to parents with schizophrenia had significantly higher levels of affective lability compared to controls. Our results add to the existing knowledge concerning underlying transdiagnostic factors and nonrandom mating in schizophrenia and bipolar disorder and highlight the need for studies of parental affective lability as a potential risk factor for offspring in families with parental schizophrenia or bipolar disorder.

Examining selection bias in a population-based cohort study of 522 children with familial high risk of schizophrenia or bipolar disorder, and controls: The Danish High Risk and Resilience Study VIA 7

PURPOSE

Knowledge about representativity of familial high-risk studies of schizophrenia and bipolar disorder is essential to generalize study conclusions. The Danish High Risk and Resilience Study (VIA 7), a population-based case-control familial high-risk study, creates a unique opportunity for combining assessment and register data to examine cohort representativity.

METHODS

Through national registers, we identified the population of 11,959 children of parents with schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) and controls from which the 522 children participating in The VIA 7 Study (202 FHR-SZ, 120 FHR-BP and 200 controls) were selected. Socio-economic and health data were obtained to compare high-risk groups and controls, and participants versus non-participants. Selection bias impact on results was analyzed through inverse probability weights.

RESULTS

In the total sample of 11,959 children, FHR-SZ and FHR-BP children had more socio-economic and health disadvantages than controls (p < 0.001 for most). VIA 7 non-participants had a poorer function, e.g. more paternal somatic and mental illness (p = 0.02 and p = 0.04 for FHR-SZ), notifications of concern (FHR-BP and PBC p < 0.001), placements out of home (p = 0.03 for FHR-SZ), and lower level of education (p ≤ 0.01 for maternal FHR-SZ and FHR-BP, p = 0.001 for paternal FHR-BP). Inverse probability weighted analyses of results generated from the VIA Study showed minor changes in study findings after adjustment for the found selection bias.

CONCLUSIONS

Familial high-risk families have multiple socio-economic and health disadvantages. In The VIA 7 Study, although comparable regarding mental illness severity after their child's birth, socioeconomic and health disadvantages are more profound amongst non-participants than amongst participants.

Intergenerational transmission of suicide attempt in a cohort of 4.4 million children

BACKGROUND

The association between suicide attempts (SAs) in parents and children is unclear, and risk indicators for intergenerational transmission remain undocumented. We aimed to assess this association, considering the child's developmental period at the time of parents' attempted suicide, and the parental relation.

METHODS

Using a prospective cohort design, nationwide population data were linked to the Psychiatric Central Register and National Patient Register for all individuals aged 10 years or older living in Denmark between 1980 and 2016. We assessed incidence rate ratios (IRRs) and cumulative hazards for children's first SA.

RESULTS

In a cohort of 4 419 651 children, 163 056 (3.7%) had experienced a parental SA. An SA was recorded among 6996 (4.3%) of the exposed children as opposed to 70112 (1.6%) in unexposed individuals. Higher rates were noted when a parental SA occurred during early childhood (0 ⩽ age < 2) [IRR, 4.7; 95% confidence interval (CI) 4.2-5.4] v. late childhood (6 ⩽ age < 13) (IRR, 3.6; 95% CI 3.4-3.8) when compared to those unexposed. Children exposed prior to age 2 had the highest rates of all sub-groups when reaching age 13-17 (IRR, 6.5; 95% CI 6.0-7.1) and 18-25 years (IRR, 6.8; 95% CI 6.2-7.4). Maternal SA (IRR, 3.4; 95% CI 3.2-3.5) was associated with higher rates than paternal (IRR, 2.8; 95% CI 2.7-2.9).

CONCLUSION

Parental SA was associated with children's own SA. Exposure during early developmental stages was associated with the highest rates. Early preventive efforts are warranted as is monitoring of suicide risk in the children from age 13.

Emotion regulation in 7-year-old children with familial high risk for schizophrenia or bipolar disorder compared to controls - The Danish High Risk and Resilience Study - VIA 7, a population-based cohort study

OBJECTIVES

Emotion regulation is a predictor of overall life outcome. Problems of emotion regulation are associated with multiple psychiatric disorders and could be a potential treatment target for improving well-being and functioning. Children at familial high risk of severe mental illness have a markedly increased risk of various psychopathology and constitute a group at significant risk of emotion regulation problems. Investigations of emotion regulation in children at familial high risk of severe mental illness are sparse.

METHODS

We applied an instrument for assessing emotion regulation, the Tangram Emotion Coding Manual (TEC-M), to a population-based cohort of 522 7-year-old children born to parents diagnosed with either schizophrenia or bipolar disorder and matched controls. The TEC-M is an ecologically valid, clinician-rated observational test measure of spontaneous emotion regulation. We aimed to compare emotion regulation between risk groups and to investigate associations between emotion regulation and psychopathology and daily life functioning, and between emotion regulation and an acknowledged questionnaire-based dysregulation profile.

RESULTS

In this early developmental phase, we found no between group differences in emotion regulation. We found a significant but weak negative association between emotion regulation and both child psychopathology and the presence of a dysregulation profile on the Child Behavior Checklist and a weak positive association between emotion regulation and current level of functioning.

CONCLUSIONS

These findings contribute to the understanding of emotion regulation in familial high-risk children and further studies of emotion regulation in children at familial high risk of severe mental illness are warranted.

Genetic assortative mating for schizophrenia and bipolar disorder

BACKGROUND

Psychiatric disorders are highly polygenic and show patterns of partner resemblance. Partner resemblance has direct population-level genetic implications if it is caused by assortative mating, but not if it is caused by convergence or social homogamy. Using genetics may help distinguish these different mechanisms. Here, we investigated whether partner resemblance for schizophrenia and bipolar disorder is influenced by assortative mating using polygenic risk scores (PRSs).

METHODS

PRSs from The Danish High-Risk and Resilience Study-VIA 7 were compared between parents in three subsamples: population-based control parent pairs (N=198), parent pairs where at least one parent had schizophrenia (N=193), and parent pairs where at least one parent had bipolar disorder (N=115).

RESULTS

The PRS for schizophrenia was predictive of schizophrenia in the full sample and showed a significant correlation between parent pairs (r=0.121, p=0.0440), indicative of assortative mating. The PRS for bipolar disorder was also correlated between parent pairs (r=0.162, p=0.0067), but it was not predictive of bipolar disorder in the full sample, limiting the interpretation.

CONCLUSIONS

Our study provides genetic evidence for assortative mating for schizophrenia, with important implications for our understanding of the genetics of schizophrenia.

Heterogeneity of social cognitive and language functions in children at familial high-risk of severe mental illness; The Danish High Risk and Resilience Study VIA 7

Cognitive heterogeneity characterizes individuals with schizophrenia and bipolar disorder; however, little is known of cognitive heterogeneity within young children at familial high-risk of schizophrenia or bipolar disorder. This study aimed to investigate heterogeneity across social cognitive and language functions in children at familial high-risk of schizophrenia or bipolar disorder, i.e. severe mental illness (FHR-SMI). This may help designate subgroups in need of intervention initiatives. A data-driven, hierarchical cluster analysis was applied across a sample of 322 children at FHR-SMI (FHR-SZ, n = 200; FHR-BP, n = 120) on measures of Theory of Mind, facial emotion recognition, social cognitive processing speed, receptive and pragmatic language. We examined differences between subgroups as well as differences between subgroups and a control group. Exploratively, the subgroups were compared in terms of social responsiveness and global functioning. A Typical-High Functioning Subgroup with intact social cognitive and language functioning (34.5%), a Mildly Impaired Subgroup with selective impairments in explicit Theory of Mind and language functioning (58.7%), and a Significantly Impaired Subgroup with social cognitive and language functioning impairments (6.8%) were identified. The subgroups differed significantly from each other and overall compares to the controls. The Significantly and Mildly Impaired Subgroups presented with poorer social responsiveness and global functioning than the Typical-High Functioning Subgroup. In young children with FHR-SMI, three subgroups with relatively homogeneous social cognitive and language functioning profiles were observed. Only a small proportion of children at FHR-SMI displayed large social cognitive and language functioning impairments in middle childhood.

The Strengths and Difficulties Questionnaire Is of Clinical Significance Regarding Emotional and Behavioral Problems in 7-Year-Old Children With Familial Risk of Schizophrenia or Bipolar Disorder and Population-Based Controls the Danish High Risk and Resilience Study-VIA 7; A Population-Based Cohort Study

BACKGROUND

Children born to parents with severe mental illness are at increased risk of mental and behavioral difficulties during childhood. We aimed to investigate the occurrence of clinically significant behavioral difficulties in 7-year-old children of parents diagnosed with schizophrenia or bipolar disorder as well as in control children by using the Strengths and Difficulties Questionnaire (SDQ). Further, we aimed to determine if the SDQ could function as a screening instrument for clinically relevant behavioral problems of children at high risk of these severe mental illnesses.

METHODS

By means of the Danish National Registers, we established a cohort of 522 7-year old children stratified by familial high risk for schizophrenia spectrum disorder (N = 202), bipolar disorder (N =120), and controls (N = 200). The child's primary caregiver completed the SDQ parent version and the Child Behavior Checklist (CBCL) while the schoolteacher completed the SDQ teacher version and the CBCL teacher equivalent; the Teachers Report Form (TRF). Finally, global functioning was assessed with the Children's Global Assessment Scale (CGAS).

RESULTS

Children with familial high risk of schizophrenia spectrum disorder or bipolar disorder have a significantly increased risk (OR = 3.8 and 2.3) of suffering clinically significant behavioral difficulties at age 7-years according to SDQ parent ratings. The SDQ discriminates with moderate to high sensitivity and high specificity between familial high-risk children with and without a psychiatric diagnosis and has overall compelling discriminatory abilities in line with the more time consuming CBCL/TRF.Conclusions Familial high-risk children have more behavioral difficulties and more frequently at a level indicative of mental illness compared to control children as measured by the SDQ. The SDQ works well as a screening instrument for clinically relevant behavioral problems in high-risk children.

Executive functions in 7-year-old children of parents with schizophrenia or bipolar disorder compared with controls: The Danish High Risk and Resilience Study-VIA 7, a population-based cohort study

Cognitive impairments are strongly associated with schizophrenia (SZ) and bipolar disorder (BP) with executive functions (EF) impairments as a likely key feature. Studies of everyday behavior rated EF in young children at familial high risk of SZ (FHR-SZ) are scarce and, to our knowledge, non-existent in young children at familial high risk of BP (FHR-BP). We aimed to compare everyday behavior-rated EF of FHR-SZ, FHR-BP, and control children. A nationwide population-based cohort of 522 7-year-old children with parents diagnosed with either SZ (N = 202) or BP (N = 120) and matched controls (N = 200) were recruited using the Danish national registries. The children's EF were assessed with the Behavior Rating Inventory of Executive Functions questionnaire rated by primary caregivers and teachers. According to primary caregiver assessments, FHR-SZ children displayed widespread EF impairments and had an odds ratio of 3.7 (2.0-6.9) of having clinically significant global EF impairments compared to controls. FHR-BP children were most severely impaired regarding EF related to emotional control and had an odds ratio of 2.5 (1.2-5.1) of clinically significant global EF impairments compared to controls. Teacher assessments were overall comparable to primary caregiver assessments but teachers rated more difficulties in the FHR-SZ group than primary caregivers. Already at age 7, children with a parental history of SZ or BP displayed significant impairments of EF in everyday-life situations. FHR-SZ children displayed widespread significant impairments of EF, whereas FHR-BP children were most severely impaired on emotional control. Clinicians should be aware of potential EF impairments in FHR children.

Parental mental illness, attendance at preventive child healthcare and dental caries in the offspring: a nation-wide population-based cohort study

PURPOSE

Severe mental illness (SMI) may interfere with parental caregiving practices and offspring development. Adhering to preventive well-child visits and maintaining good oral hygiene during early childhood requires parental involvement. Whether these activities are affected by parental SMI is unclear. The purpose of the present study was to determine whether children exposed to parental SMI are at increased risk of non-attendance to preventive well-child visits and vaccinations at age 0-5 years and of child dental caries experience at age 5 years. Furthermore, interactions between maternal psychiatric and sociodemographic variables in relation to an adverse child outcome were assessed.

METHODS

Data were obtained from national Danish health registers. All children born in Denmark between January 1997 and December 2010 were followed from birth until their 6th birthday.

RESULTS

679,339 children were included in the study (51% male). Of these, 49,059 children (7.8%) had at least one parent with a lifetime SMI diagnosis. Children of parents with SMI had elevated odds of missing well-child visits and vaccinations (OR 1.41; 95% CI 1.39-1.44, p < 0.0001), and of child dental caries (OR 1.58; 95% CI 1.55-1.62, p < 0.0001). In the presence of maternal SMI, low socioeconomic classification and single-mother status added more to the elevated risk than specific maternal diagnosis or timing of last psychiatric contact.

CONCLUSION

Parents with SMI are less compliant with preventive child healthcare activities than parents without SMI. This indicates a need for practical support to these families in order to prevent inequality in health among their offspring.

A Nationwide Cohort Study of Nonrandom Mating in Schizophrenia and Bipolar Disorder

Nonrandom mating in parents with schizophrenia or bipolar disorder increases the population-level genetic variance among the offspring generation and creates familial (risk) environments likely to be shaped by specific conditions. The objective of this study was to investigate the occurrence of mental disorder and levels of cognitive and social functioning in individuals who have children by partners with schizophrenia or bipolar disorder compared to controls. The Danish High Risk and Resilience Study VIA 7 is a population-based cohort study conducted in Denmark between 2013 and 2016. This study focus on parents diagnosed with schizophrenia (n = 150) or bipolar disorder (n = 100) and control parents (n = 182), as well as their partners without schizophrenia or bipolar disorder (n = 440). We used linear mixed-effect models, and main outcomes were mental disorders, intelligence, processing speed, verbal working memory, and social functioning. We found that parents having children by a partner with schizophrenia or bipolar disorder more often fulfilled the criteria for a mental disorder and had poorer social functioning compared to parents having children by a partner without schizophrenia or bipolar disorder. Furthermore, parents having children by a partner with schizophrenia performed poorer on processing speed compared to parents in the control group. The presence of nonrandom mating found in this study has implications for our understanding of familial transmission of these disorders and our findings should be considered in future investigations of potential risk factors for children with a parent with schizophrenia or bipolar disorder.

Quantitative genome-wide association analyses of receptive language in the Danish High Risk and Resilience Study

BACKGROUND

One of the most basic human traits is language. Linguistic ability, and disability, have been shown to have a strong genetic component in family and twin studies, but molecular genetic studies of language phenotypes are scarce, relative to studies of other cognitive traits and neurodevelopmental phenotypes. Moreover, most genetic studies examining such phenotypes do not incorporate parent-of-origin effects, which could account for some of the heritability of the investigated trait. We performed a genome-wide association study of receptive language, examining both child genetic effects and parent-of-origin effects.

RESULTS

Using a family-based cohort with 400 children with receptive language scores, we found a genome-wide significant paternal parent-of-origin effect with a SNP, rs11787922, on chromosome 9q21.31, whereby the T allele reduced the mean receptive language score by ~ 23, constituting a reduction of more than 1.5 times the population SD (P = 1.04 × 10-8). We further confirmed that this association was not driven by broader neurodevelopmental diagnoses in the child or a family history of psychiatric diagnoses by incorporating covariates for the above and repeating the analysis.

CONCLUSIONS

Our study reports a genome-wide significant association for receptive language skills; to our knowledge, this is the first documented genome-wide significant association for this phenotype. Furthermore, our study illustrates the importance of considering parent-of-origin effects in association studies, particularly in the case of cognitive or neurodevelopmental traits, in which parental genetic data are not always incorporated.

Quality of life and self-esteem in 7-year-old children with familial high risk of schizophrenia or bipolar disorder: the Danish High Risk and Resilience Study-VIA 7-a population-based cohort study

It is well established that children with familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) have a higher risk of developing mental disorders, however, little is known of to what degree the genetic and environmental vulnerabilities affect the quality of life and self-esteem of these children. We aimed to compare the quality of life and self-esteem between children with FHR-SZ or FHR-BP and controls. We used Danish nationwide registers to retrieve a cohort of 522 7-year-old children with FHR-SZ or FHR-BP and controls. Quality of life was assessed with the 'Health-related Quality of Life Screening Instrument', KIDSCREEN-27, and the scale 'Social Acceptance (Bullying)' from the KIDSCREEN-52. Self-esteem was assessed with the self-report scale 'I think I am'. Assessors were blind to familial risk status of the children. Children with FHR-SZ displayed lower levels of the general quality of life, as well as lower scores on the 'Psychological Well-being' scale and the 'School Environment' scale of the KIDSCREEN-27 compared with controls. Both children with FHR-SZ and FHR-BP reported more bullying victimization compared with controls. Children with FHR-SZ reported lower self-esteem on the total scale of 'I think I am', as well as on the 'Skills and talents', the 'Psychological well-being', and the 'Relationships with others' subscales compared with controls. The findings of lower quality of life and self-esteem in children with FHR-SZ together with more bullying victimization in both familial high-risk groups call for studies on low risk, early intervention strategies towards this group of vulnerable children.

Morbidity and Mortality in the Children and Young Adult Offspring of Parents With Schizophrenia or Affective Disorders-A Nationwide Register-Based Cohort Study in 2 Million Individuals

BACKGROUND

The offspring of parents with severe mental illness (SMI) are at higher risk of mortality and of developing certain somatic diseases. However, across the full spectrum of somatic illness, there remains a gap in knowledge regarding morbidity.

METHODS

We conducted a register-based nationwide cohort study of all 2 000 694 individuals born in Denmark between 1982 and 2012. Maximum age of offspring at follow-up was 30 years. Information on parents' psychiatric diagnoses of schizophrenia, bipolar disorder, and unipolar depression was retrieved from the Psychiatric Central Register. We estimated incidence rate ratio (IRR), cumulative incidence percentage and mortality rate ratio of first hospital contact for a broad spectrum of somatic illnesses according to the International Statistical Classification of Diseases and Related Health Problems. Analyses were adjusted for important confounders.

RESULTS

Offspring of individuals with SMI had higher risk of somatic hospital contacts IRR: 1.17 (95% CI: 1.16-1.18) with maternal depression being associated with the highest IRR (1.22, 95% CI: 1.20-1.24). Offspring of parents with SMI had higher risk within most broad diagnostic categories with highest IRRs for unclassified somatic diagnoses, infections and endocrine diseases ranging from 1.27 (95% CI: 1.25-1.28) to 1.26 (95% CI: 1.23-1.29) (all P < .0001). Morbidity was particularly increased in children aged 0-7 years. The mortality rate ratio associated with parental SMI was 1.31 (95% CI: 1.21-1.41) with excess mortality mainly due to unnatural causes.

CONCLUSION

Our findings indicate that offspring of parents with SMI experienced increased mortality and somatic morbidity warranting heightened vigilance and support for this population.

Language deficits in specific language impairment, attention deficit/hyperactivity disorder, and autism spectrum disorder: An analysis of polygenic risk

Language is one of the cognitive domains often impaired across many neurodevelopmental disorders. While for some disorders the linguistic deficit is the primary impairment (e.g., specific language impairment, SLI), for others it may accompany broader behavioral problems (e.g., autism). The precise nature of this phenotypic overlap has been the subject of debate. Moreover, several studies have found genetic overlaps across neurodevelopmental disorders. This raises the question of whether these genetic overlaps may correlate with phenotypic overlaps and, if so, in what manner. Here, we apply a genome‐wide approach to the study of the linguistic deficit in SLI, autism spectrum disorder (ASD), and attention deficit/hyperactivity disorder (ADHD). Using a discovery genome‐wide association study of SLI, we generate polygenic risk scores (PRS) in an independent sample which includes children with language impairment, SLI, ASD or ADHD and age‐matched controls and perform regression analyses across groups. The SLI‐trained PRS significantly predicted risk in the SLI case–control group (adjusted R² = 6.24%; P = 0.024) but not in the ASD or ADHD case‐control groups (adjusted R² = 0.0004%, 0.01%; P = 0.984, 0.889, respectively) nor for height, used as a negative control (R² = 0.2%; P = 0.452). Additionally, there was a significant difference in the normalized PRS between children with SLI and children with ASD (common language effect size = 0.66; P = 0.044). Our study suggests no additive common‐variant genetic overlap between SLI and ASD and ADHD. This is discussed in the context of phenotypic studies of SLI and related disorders. Autism Res 2020, 13: 369–381. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.

Lay Summary

Language deficits are characteristic of specific language impairment (SLI), but may also be found in other neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD). Many studies examined the overlaps and differences across the language deficits in these disorders, but few studies have examined the genetic aspect thereof. In this study, we use a genome‐wide approach to evaluate whether common genetic variants increasing risk of SLI may also be associated with ASD and ADHD in the same manner. Our results suggest that this is not the case, and we discuss this finding in the context of theories concerning the etiologies of these disorders.

Home visits in the Danish High Risk and Resilience Study - VIA 7: assessment of the home environment of 508 7-year-old children born to parents diagnosed with schizophrenia or bipolar disorder

OBJECTIVE

The home environment provided by the caregivers of a child is an influential single factor for development and well-being. We aimed to compare the quality of the home environment of children at familial high risk of schizophrenia or bipolar disorder with population-based controls.

METHODS

Danish nationwide registers were used to retrieve a cohort of 522 7-year-old children of parents diagnosed with schizophrenia (N = 202), bipolar disorder (N = 120) or none of these diagnoses (N = 200). The home environment was assessed using the Middle Childhood-Home Observation for Measurement of the Environment Inventory (MC-HOME Inventory).

RESULTS

The proportion of children living in home environments that were evaluated not to meet the needs of a 7-year-old child was significantly larger in the two familial high-risk groups. This was true for 21% of the children with familial predisposition for schizophrenia and 7% of children with familial disposition for bipolar disorder.

CONCLUSION

Children born to parents diagnosed with schizophrenia and to a lesser extent bipolar disorder are at an increased risk of growing up in a home environment with an insufficient level of stimulation and support. Identifying families with inadequate home environments is a necessary step towards specialized help and support to at-risk families.

VIA Family-a family-based early intervention versus treatment as usual for familial high-risk children: a study protocol for a randomized clinical trial

BACKGROUND

Children born to parents with a severe mental illness, like schizophrenia, bipolar disorder, or major recurrent depression, have an increased risk of developing a mental illness themselves during life. These children are also more likely to have developmental delays, cognitive disabilities, or social problems, and they may have a higher risk than the background population of experiencing adverse life events. This is due to both genetic and environmental factors, but despite the well-documented increased risk for children with a familial high risk, no family-based early intervention has been developed for them. This study aims to investigate the effect of an early intervention that focuses on reducing risk and increasing resilience for children in families where at least one parent has a severe mental illness.

METHODS/DESIGN

The study is a randomized clinical trial with 100 children aged 6-12 with familial high risk. It is performed in the context of the Danish health-care system. Families will be recruited from registers or be referred from the primary sector or hospitals. The children and their parents will be assessed at baseline and thereafter randomized and allocated to either treatment as usual or VIA Family. The intervention group will be assigned to a multidisciplinary team of specialists from adult mental health services, child and adolescent mental health services, and social services. This team will provide the basic treatment elements: case management, psychoeducation for the whole family, parental training, a safety plan, and potentially an early intervention if the child has mental problems. The study period is 18 months for both groups, and all participants will be assessed at baseline and after 18 months. The primary outcome measure will be daily functioning of the child, and the secondary measures are the psychopathology of the child, days of absence from school, family functioning, child's home environment, and parental stress.

DISCUSSION

This study is to our knowledge the first to explore the effects of a multidisciplinary team intervention that provides an intensive and flexible support to match the families' needs for children with a familial high risk for severe mental illness. The study will provide important knowledge about the potential for increasing resilience and reducing risk for children by supporting the whole family. However, a longer follow-up period may be needed.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT03497663 . Registered on 13 April 2018.

The Danish High Risk and Resilience Study-VIA 11: Study Protocol for the First Follow-Up of the VIA 7 Cohort -522 Children Born to Parents With Schizophrenia Spectrum Disorders or Bipolar Disorder and Controls Being Re-examined for the First Time at Age 11

Introduction: Offspring of parents with severe mental illness have an increased risk of developing mental illnesses themselves. Familial high risk cohorts give a unique opportunity for studying the development over time, both the illness that the individual is predisposed for and any other diagnoses. These studies can also increase our knowledge of etiology of severe mental illness and provide knowledge about the underlying mechanisms before illness develops. Interventions targeting this group are often proposed due to the potential possibility of prevention, but evidence about timing and content is lacking. Method: A large, representative cohort of 522 7-year old children born to parents with schizophrenia, bipolar disorder or controls was established based on Danish registers. A comprehensive baseline assessment including neurocognition, motor functioning, psychopathology, home environment, sociodemographic data, and genetic information was conducted from January 1, 2013 to January 31, 2016. This study is the first follow-up of the cohort, carried out when the children turn 11 years of age. By assessing the cohort at this age, we will evaluate the children twice before puberty. All instruments have been selected with a longitudinal perspective and most of them are identical to those used at inclusion into the study at age 7. A diagnostic interview, motor tests, and a large cognitive battery are conducted along with home visits and information from teachers. This time we examine the children's brains by magnetic resonance scans and electroencephalograms. Measures of physical activity and sleep are captured by a chip placed on the body, while we obtain biological assays by collecting blood samples from the children. Discussion: Findings from the VIA 7 study revealed large variations across domains between children born to parents with schizophrenia, bipolar and controls, respectively. This study will further determine whether the children at familial risk reveal delayed developmental courses, but catch up at age 11, or whether the discrepancies between the groups have grown even larger. We will compare subgroups within each of the familial high risk groups in order to investigate aspects of resilience. Data on brain structure and physical parameters will add a neurobiological dimension to the study.

Incidence of child and adolescent mental disorders in children aged 0-17 with familial high risk for severe mental illness - A Danish register study

BACKGROUND

Offspring of parents with severe mental illness (SMI: schizophrenia, bipolar disorder or major depressive disorder) have an increased risk of developing mental disorder themselves. In childhood they may have neurodevelopmental delays, cognitive deficits and social adversities. We aimed to investigate if these individuals are more at risk of being diagnosed with a mental disorder during childhood/adolescence in a national sample.

METHODS

By linking Danish registers we established a cohort consisting of all persons born to parents with SMI with those born to parents without SMI serving as a reference group. Incidence rate ratios (IRRs) for offspring diagnosed with a mental disorder by parental mental disorder were calculated.

RESULTS

Offspring of parents with SMI showed increased IRR for all diagnoses of child and adolescent mental disorders compared to the reference group. Offspring of mothers with schizophrenia had IRR of 2.60 (CI: 2.50-2.70, N=2550) of having any diagnoses, for children of fathers with schizophrenia IRR was 2.06 (CI: 1.97-2.16, N=1901) and for offspring of two parents with schizophrenia IRR was 4.57 (CI: 3.94-5.31, N=175). For individuals with a mother with bipolar disorder the IRR was 2.29 (CI: 2.09-2.50, N=502), with a father 1.77 (CI: 1.74-1.87, N=320), whereas the IRR was 2.96 (CI: 2.63-3.34, N=264) if both parents had unipolar depression.

DISCUSSION

Offspring of parents with a SMI have a higher risk of being diagnosed with any child and adolescent mental disorder. The IRRs for all diagnoses during childhood were increased by a factor 2-4. Having two ill parents increased the IRR.

Stability and development of psychotic symptoms and the use of antipsychotic medication - long-term follow-up

BACKGROUND

Few studies have evaluated the development in the use of antipsychotic medication and psychotic symptoms in patients with first-episode psychosis on a long-term basis. Our objective was to investigate how psychotic symptoms and the use of antipsychotic medication changed over a 10-year period in a cohort of patients with first-episode psychosis.

METHOD

The study is a longitudinal prospective cohort study over 10 years with follow-ups at years 1, 2, 5 and 10. A total of 496 patients with first-episode psychosis were included in a multi-centre study initiated between 1998 and 2000 in Copenhagen and Aarhus, Denmark.

RESULTS

At all follow-ups, a large proportion (20-30%) of patients had remission of psychotic symptoms without use of antipsychotic medication at the time of the follow-up. Patients who were in this group at the 5-year follow-up had an 87% [95% confidence interval (CI) 77-96%] chance of being in the same group at the 10-year follow-up. This stability was also the case for patients who had psychotic symptoms and were treated with antipsychotic medication at year 5, where there was a 67% (95% CI 56-78%) probability of being in this group at the consecutive follow-up.

CONCLUSIONS

A large group of patients with psychotic illness were in remission without the use of antipsychotic medication, peaking at year 10. Overall there was a large degree of stability in disease courses over the 10-year period. These results suggest that the long-term outcome of psychotic illness is heterogeneous and further investigation on a more individualized approach to long-term treatment is needed.

Impairments of motor function among children with a familial risk of schizophrenia or bipolar disorder at 7 years old in Denmark: an observational cohort study

BACKGROUND

Owing to the genetic overlap between schizophrenia and bipolar disorder, we aimed to assess domain-specific motor aberrations and disorder specificity among 7-year-old children with a familial risk of schizophrenia or bipolar disorder by comparing children in familial risk groups with each other and with children not in these risk groups.

METHODS

In the Danish High Risk and Resilience Study, we established a cohort of 7-year-old children with no, one, or two parents with schizophrenia or bipolar disorder in Denmark between Jan 1, 2013, and Jan 31, 2016. We matched children of parents diagnosed with schizophrenia to children of parents without schizophrenia on the basis of their home address, age, and sex. Even though we did not match children of parents with bipolar disorder directly to controls because of resource constraints, we only recruited children into the three groups who did not differ in terms of age, sex, and urbanicity. We investigated motor function in children using the Movement Assessment Battery for Children-Second Edition. Motor function raters were masked to participants' clinical risk status during assessments. We assessed the effects of familial risk group in a mixed-model analysis with repeated measures with an unstructured variance component matrix.

FINDINGS

We studied 514 children (198 [39%] children of parents with schizophrenia, 119 [23%] of parents with bipolar disorder, and 197 [38%] of parents without schizophrenia or bipolar disorder). Children of parents with schizophrenia showed impaired motor performance compared with those of parents without in the subdomains of manual dexterity (mean difference -1·42 [95% CI -2·08 to -0·77]; p<0·0001) and balance (-1·38 [-2·03 to -0·72]; p<0·0001), but not of aiming and catching (-0·39 [-0·97 to 0·19]; p=0·18). Children of parents with bipolar disorder did not show any significant difference in motor performance to children of parents without in the subdomains of manual dexterity (-0·69 [-1·44 to 0·07]; p=0·08), balance (-0·68 [-1·44 to 0·08]; p=0·08), and aiming and catching (-0·36 [-1·03 to 0·31]; p=0·29). Comparison of familial risk groups of mental disorders revealed no significant differences in the subdomains of manual dexterity (-0·74 [-1·49 to 0·02]; p=0·06), balance (-0·70 [-1·46 to 0·06]; p=0·07), or aiming and catching (-0·03 [-0·70 to 0·63]; p=0·92).

INTERPRETATION

Motor abnormalities in children with a familial risk of schizophrenia are specific at 7 years of age with respect to fine motor function and balance, but non-specific with respect to familial risk of bipolar disorder. Clinicians should be aware of motor symptoms and refer children with definite motor problems (below the fifth percentile) to a child physiotherapist.

FUNDING

Mental Health Services of the Capital Region of Denmark, Aarhus University, and the Lundbeck Foundation Initiative for Integrative Psychiatric Research.

The Danish High Risk and Resilience Study--VIA 7--a cohort study of 520 7-year-old children born of parents diagnosed with either schizophrenia, bipolar disorder or neither of these two mental disorders

BACKGROUND

Severe mental illnesses like schizophrenia and bipolar disorder are known to be diseases that to some extent, but not entirely can be understood genetically. The dominating hypothesis is that these disorders should be understood in a neurodevelopmental perspective where genes and environment as well as gene-environment-interactions contribute to the risk of developing the disease. We aim to analyse the influences of genetic risk and environmental factors in a population of 520 7-year-old children with either 0, 1 or 2 parents diagnosed with schizophrenia spectrum psychosis or bipolar disorder on mental health and level of functioning. We hypothesize that a larger proportion of children growing up with an ill parent will display abnormal or delayed development, behavioural problems or psychiatric symptoms compared to the healthy controls.

METHODS/DESIGN

We are establishing a cohort of 5207 year old children and both their parents for a comprehensive investigation with main outcome measures being neurocognition, behaviour, psychopathology and neuromotor development of the child. Parents and children are examined with a comprehensive battery of instruments and are asked for genetic material (saliva or blood) for genetic analyses. The participants are recruited via Danish registers to ensure representativity. Data from registers concerning social status, birth complications, somatic illnesses and hospitalization are included in the database. Psychological and relational factors like emotional climate in the family, degree of stimulation and support in the home and attachment style are also investigated.

DISCUSSION

Data collection started January 1, 2013, and is successfully ongoing. By Aug 2015 424 families are included. About 20% of the invited families decline to participate, equal for all groups.