The development in rating-based executive functions in children at familial high risk of schizophrenia or bipolar disorder from age 7 to age 11: the Danish high risk and resilience study

Executive functions (EF) deficits are well documented in children at familial high risk of schizophrenia (FHR-SZ), and to a lesser degree in children at familial high risk of bipolar disorder (FHR-BP). The aim of this study was to assess EF development in preadolescent children at FHR-SZ, FHR-BP and population-based controls (PBC) using a multi-informant rating scale. A total of 519 children (FHR-SZ, n = 201; FHR-BP, n = 119; PBC, n = 199) participated at age 7, at age 11 or at both time points. Caregivers and teachers completed the Behavior Rating Inventory of Executive Functions (BRIEF). The developmental pattern from age 7 to age 11, did not differ between groups. At age 11, caregivers and teachers rated children at FHR-SZ as having widespread EF deficits. A higher proportion of children at FHR-SZ had clinically significant scores on the General executive composite (GEC) and all BRIEF indices compared to PBC. According to the caregivers, children at FHR-BP had significantly more EF deficits than PBC on 9 out of 13 BRIEF scales, whereas according to teachers, they only had significantly more deficits on one subdomain (Initiate). Likewise, caregivers rated a significantly higher proportion of children at FHR-BP above the clinical cut-off on the GEC and Metacognition index, compared to PBC, whereas there were no significant differences according to teachers. This study highlights the relevance of including multi-informant rating scales in the assessment of EF in children at FHR-SZ and FHR-BP. The results imply a need to identify children at high risk who would benefit from targeted intervention.

Attachment representations in 7-year-old children at familial high risk of schizophrenia or bipolar disorder: Associations with mental disorders and daily functioning: The Danish High Risk and Resilience Study, VIA 7-A population-based cohort study

BACKGROUND

Attachment quality may affect psychological functioning. However, evidence on attachment representations and their correlates in children born to parents with schizophrenia and bipolar disorder is sparse.

METHODS

We compared attachment representations in a Danish sample of 482 children aged 7 years at familial high risk of schizophrenia, bipolar disorder, and population-based controls and examined associations between attachment and mental disorders and daily functioning. Attachment representations were examined with the Story Stem Assessment Profile (SSAP). Mental disorders were ascertained in diagnostic interviews. Daily functioning was assessed with the Children's Global Assessment Scale.

RESULTS

We found no between-group differences in attachment. Higher levels of secure attachment were associated with decreased risk of concurrent mental disorders in the schizophrenia high-risk group. Higher levels of insecure and disorganized attachment were associated with increased risk of mental disorders across the cohort. Higher levels of secure and insecure attachment were associated with better and poorer daily functioning, respectively. In the current study, results regarding defensive avoidance could not be reported due to methodological limitations.

CONCLUSION

Familial high risk of schizophrenia (FHR-SZ) or bipolar disorder is not associated with less secure or more insecure attachment at age 7. Insecure and disorganized attachment representations index risk of mental disorders and poorer functioning. Secure attachment may be a protective factor against mental disorders in children at FHR-SZ. Validation of the SSAP is needed.

Hair cortisol concentrations and perceived stress in 7-year-old children at familial high-risk of schizophrenia or bipolar disorder

BACKGROUND

Dysregulation of the HPA-axis, perceived stress and interpersonal trauma are associated with an elevated risk for schizophrenia and bipolar disorder. Being at familial high-risk of these two mental disorders also constitutes an increased risk. In this study, we aimed to investigate hair cortisol concentrations and perceived stress among 7-year-old children at familial high-risk of schizophrenia (FHR-SZ), bipolar disorder (FHR-BP), and population-based controls (controls).

METHODS

A total of 515 children (mean age 7.8, SD 0.2) from baseline assessment of the Danish High Risk and Resilience Study - VIA 7 participated in this study. Hair cortisol concentrations were analyzed among 322 children (FHR-SZ; N = 111, FHR-BP; N = 82, controls; N = 129). Perceived stress was assessed with the Daily Life Stressor Scale including 512 children (FHR-SZ; N = 195, FHR-BP; N = 118, controls; N = 199). Interpersonal trauma was measured with face-to-face interviews.

RESULTS

Seven-year-old children at FHR-SZ or FHR-BP did not have a higher level of hair cortisol concentrations compared with controls (FHR-SZ: mean: 5.10, 95%CI 3.69-6.52; FHR-BP: mean: 5.01, 95%CI 3.27-6.72; controls: mean: 4.51, 95%CI 3.61-5.40; p = 0.77). Self-reported perceived stress was higher among children at FHR-SZ and FHR-BP compared with controls (FHR-SZ: mean: 12.09, 95%CI 10.99-13.19; FHR-BP: mean: 10.69, 95%CI 9.38-11.99; controls: mean: 8.90, 95%CI 8.13-9.68; p < 0.001). There was no significant association between hair cortisol concentrations and perceived stress (p = 0.84). Exploratory analyses revealed that interpersonal trauma exposure was neither associated with elevated hair cortisol nor perceived stress.

CONCLUSIONS

Children at FHR-SZ and FHR-BP did not exhibit higher levels of hair cortisol concentrations at age 7, while both FHR-groups had higher level of self-reported perceived stress compared with controls. Early attention to stress in children at FHR is crucial and these vulnerabilities should be targeted in future interventions studies.

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.

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.

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.

Neurocognitive heterogeneity in 7-year-old children at familial high risk of schizophrenia or bipolar disorder: The Danish high risk and resilience study - VIA 7

BACKGROUND

Studies of neurocognitive heterogeneity in young children at familial high-risk of bipolar disorder (FHR-BP) or schizophrenia (FHR-SZ) are important to investigate inter-individual neurocognitive differences. We aimed to identify neurocognitive subgroups, describe prevalence of FHR-BP or FHR-SZ children herein, and examine risk ratios (RR) compared with controls.

METHODS

In a population-based cohort of 514 7-year-old children (197 FHR-SZ, 118 FHR-BP, and 199 matched controls) we used hierarchical cluster analyses to identify subgroups across 14 neurocognitive indices.

RESULTS

Three neurocognitive subgroups were derived: A Mildly Impaired (30%), Typical (51%), and Above Average subgroup (19%). The Mildly Impaired subgroup significantly underperformed controls (Cohen d = 0.11-1.45; Ps < 0.001) except in set-shifting (P = .84). FHR-SZ children were significantly more prevalent in the Mildly Impaired subgroup; FHR-BP children were more so in the Above Average subgroup (X² (2, N = 315) = 9.64, P < .01). 79.7% FHR-BP and 64.6% FHR-SZ children demonstrated typical or above average neurocognitive functions. Neurocognitive heterogeneity related significantly to concurrent functioning, psychopathology severity, home environment adequacy, and polygenic scores for schizophrenia (Ps <. 01). Compared with controls, FHR-SZ and FHR-BP children had a 93% (RR, 1.93; 95% CI, 1.40-2.64) and 8% (RR, 1.08; 95% CI, 0.71-1.66) increased risk of Mildly Impaired subgroup membership.

LIMITATIONS

Limitations include the cross-sectional design and smaller FHR-BP sample size.

CONCLUSIONS

Identification of neurocognitive heterogeneity in preadolescent children at FHR-BP or FHR-SZ may ease stigma and enable pre-emptive interventions to enhance neurocognitive functioning and resilience to mental illness in the impaired sub-population.

Childhood trauma in children at familial high risk of schizophrenia or bipolar disorder: A longitudinal study. The Danish High Risk and Resilience Study - VIA 7 and VIA 11

OBJECTIVES

Childhood trauma increases the risk of developing mental illness as does being born to parents with schizophrenia or bipolar disorder. We aimed to compare prevalence of lifetime childhood trauma among 11-year-old children at familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) compared with population-based controls (PBCs).

DESIGN

The study is a longitudinal, prospective cohort study of children at FHR-SZ, FHR-BP, and PBCs.

METHODS

A cohort of 512 children at FHR-SZ (N = 199), FHR-BP (N = 118), and PBCs (N = 195) were examined at baseline (mean age 7.8, SD 0.2) and 451 children at FHR-SZ (N = 172), FHR-BP (N = 104), and PBCs (N = 175) were examined at four-year follow-up (mean age 11.9, SD 0.2, retention rate 87.3%). Childhood trauma was measured with a semi-structured interview.

RESULTS

Children at FHR-BP had an elevated risk of exposure to any lifetime trauma (age 0-11 years) compared with PBCs (OR 2.082, 95%CI 1.223-3.545, p = .007) measured with binary logistic regression. One-way ANOVA revealed that both FHR-groups had a higher lifetime prevalence of exposure to a greater number of types of trauma compared with PBCs (FHR-SZ: observed mean: 1.53, 95%CI 1.29-1.77; FHR-BP: observed mean: 1.56, 95%CI 1.26-1.85; PBCs: observed mean: 0.99, 95%CI 0.82-1.17; p < .001). Binary logistic regression showed that the lifetime risk of exposure to interpersonal trauma (age 0-11 years) was elevated for both FHR-groups (FHR-SZ: OR 3.773, 95%CI 2.122-6.710, p < .001; FHR-BP: OR 3.602, 95%CI 1.913-6.783, p < .001).

CONCLUSIONS

Children at FHR-SZ and FHR-BP are at increased risk for being exposed to childhood trauma compared with PBCs. This study underscores the need for early detection, support, and prevention of childhood trauma in children at FHR-SZ and FHR-BP.

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.

Decision making and its associations to neurocognitive functions, psychopathology, and the home environment in seven-year-old children at familial high risk of schizophrenia or bipolar disorder: The Danish High Risk and Resilience Study VIA 7

BACKGROUND

Slower and suboptimal decision making has been identified in adults with schizophrenia and bipolar disorder. Owing to the limited evidence on decision making in first-degree relatives, we aimed to investigate, whether alterations in decision making are present in young children at familial high risk of bipolar disorder or schizophrenia.

METHODS

In this population-based cohort study we assessed decision making in 197 children at familial high risk of schizophrenia (FHR-SZ), 115 children at familial high risk of bipolar disorder (FHR-BP), and 190 controls aged seven using the Cambridge Gambling Task. Potential associations to neurocognition, psychopathology, and the home environment were investigated.

RESULTS

Children at FHR-SZ or FHR-BP displayed intact decision making. Quality of decision making showed significant but weak cross-sectional associations to neurocognition and adequacy of the home environment. Associations to aspects of executive functions and the home environment differed across groups.

LIMITATIONS

Due to the cross-sectional nature of this study, the predictive value of efficient and inefficient decision making remains to be investigated in planned follow-up studies of this cohort.

CONCLUSIONS

Young children at FHR-SZ or FHR-BP do not differ from controls in decision making efficacy, which does not appear to be an early risk marker of bipolar disorder or schizophrenia. Decision making is weakly associated to neurocognition and the home environment, but not to general intelligence or psychopathology.

Development of visual attention from age 7 to age 12 in children with familial high risk for schizophrenia or bipolar disorder

BACKGROUND

Children with familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) are at increased risk of developing similar disorders and show cognitive deficits during childhood. The aim of this paper is to investigate visual attention and its developmental trajectories in children with FHR-SZ and with FHR-BP to increase our knowledge about potential cognitive endophenotypes of these two disorders.

METHODS

We compared the performance of 89 children with FHR-SZ (N = 32), FHR-BP (N = 22), and population-based controls (PBC, N = 35) at age 7 to that at age 12 as well as including 133 12-year-old children with FHR-SZ (N = 50), FHR-BP (N = 43) and PBC (N = 40) to investigate visual attention, as part of the Danish High Risk and Resilience Study. We used the TVA-based whole report paradigm, based on the Bundesen's Theory of Visual Attention (TVA) to investigate visual attention.

RESULTS

Children with FHR-SZ that showed deficits in visual processing speed at age 7 improved to a level that was not significantly different from controls at age 12. All children improved over time. We found no attentional deficits in FHR children at age 12.

CONCLUSIONS

On visual attention, children with FHR-SZ did not show developmental deficits or lags and, together with children with FHR-BP, they develop similarly to control children between age 7 to age 12. This emphasizes the potential of beneficial neuroplastic changes in cognitive deficits found at younger ages in children with FHR-SZ. It also highlights the importance of identifying and characterizing cognitive developmental trajectories of high-risk children and provides hope that visual attention may develop appropriately in these groups.

Odor identification in 7-year-old children at familial high risk of schizophrenia or bipolar disorder - the Danish high risk and resilience study VIA 7

BACKGROUND

Odor identification deficits occur in individuals with schizophrenia and their unaffected first-degree relatives, while deficits are less pronounced in individuals with bipolar disorder. We hypothesized that children at familial high-risk for schizophrenia (FHR-SZ) show odor identification deficits compared to population-based controls and that children at familial high-risk for bipolar disorder (FHR-BP) perform intermediate.

METHODS

Odor identification was assessed at age 7 in 184 children with FHR-SZ, 106 children with FHR-BP, and 186 population-based controls with the Brief Smell Identification Test. Dimensional and predefined categorical outcomes were used in the analyses. Potential relationships with psychopathological, cognitive, and home environmental variables were conducted using hierarchical and logistic multiple regression analyses.

RESULTS

ANOVA revealed no between-group differences in odor identification. Using the recommended cut-off (below 5), we found a significantly greater proportion of boys at FHR-SZ than population-based boys with an abnormal odor identification (p = .013). However, a supplementary analysis using a Danish-based cut-off (below 4) did not support this. All children showed significant, positive associations of odor identification with female gender, social responsiveness, and verbal working memory. Lower social responsiveness predicted abnormal odor identification in boys at FHR-SZ, only using the recommended cut-off.

CONCLUSIONS

Odor identification efficacy and risk status appear independent in this early developmental phase. Using the recommended threshold, abnormal odor identification is more frequent in young boys at FHR-SZ than in population-based boys and is linked to lower social responsiveness. The validity of these results is questioned by non-significant differences in the rates when using an exploratory Danish-based threshold.

Visual attention in 7-year-old children at familial high risk of schizophrenia or bipolar disorder: The Danish high risk and resilience study VIA 7

BACKGROUND

Attention deficits are found in children at familial high risk of schizophrenia (FHR-SZ) and bipolar disorder (FHR-BP) using assessment methods relying on motor-based response latency. This study compares visual attention functions in children at FHR-SZ or FHR-BP with controls using an unspeeded task unconfounded by motor components.

METHODS

Visual attention was assessed in 133 7-year-old children at FHR-SZ (N = 56) or FHR-BP (N = 32), and controls (N = 45) using the unspeeded paradigm, TVA-based whole report. We compared four parameters of visual attention: visual processing speed, visual short-term memory, threshold for visual perception, and error rate. Further, we investigated their potential relationships with severity of psychopathology, adequacy of the home environment, and neurocognitive measures.

RESULTS

Children at FHR-SZ displayed significant deficits in perceptual processing speed of visual attention compared with controls (p < .001; d = 0.75) as did children at FHR-BP (p < .05; d = 0.54). Visual processing speed was significantly associated with spatial working memory (β = -0.23; t(68) = -3.34, p = .01) and psychomotor processing speed (β = 0.14, t(67) = 2.11, p < .05).

LIMITATIONS

Larger group sizes would have permitted inclusion of more predictors in the search for neurocognitive and other factors associated with the parameters of TVA-based whole report.

CONCLUSIONS

Young children at FHR-SZ and FHR-BP display significant deficits in processing speed of visual attention, which may reflect the effect of shared vulnerability risk genes. Early identification of children at FHR-SZ and FHR-BP with perceptual processing speed impairments may represent a low-cost basis for low-risk interventions.

Assessment of Neurocognitive Functions in 7-Year-Old Children at Familial High Risk for Schizophrenia or Bipolar Disorder: The Danish High Risk and Resilience Study VIA 7

IMPORTANCE

Children at familial high risk of schizophrenia spectrum disorders (FHR-SZ) or bipolar disorder (FHR-BP) exhibit neurocognitive impairments. Large studies of neurocognition in young children at familial high risk at the same age are important to differentiate the pathophysiology and developmental trajectory of these 2 groups.

OBJECTIVE

To characterize neurocognitive functions in 7-year-old children with FHR-SZ or FHR-BP and a control population.

DESIGN, SETTING, AND PARTICIPANTS

This multisite population-based cohort study collected data from January 1, 2013, to January 31, 2016, in the first wave of the Danish High Risk and Resilience Study VIA 7 at 2 university hospital research sites in Copenhagen and Aarhus using Danish registries. Participants (n = 514) included 197 children with FHR-SZ, 118 with FHR-BP, and 199 controls matched with the FHR-SZ group for age, sex, and municipality. Assessors were blinded to risk status.

EXPOSURES

Parents with schizophrenia, bipolar disorder, or neither diagnosis.

MAIN OUTCOMES AND MEASURES

Neurocognitive functions were measured across 23 tests. Four neurocognitive domains were derived by principal component analysis, including processing speed and working memory, verbal functions, executive and visuospatial functions, and declarative memory and attention.

RESULTS

A total of 514 children aged 7 years were included in the analysis (46.3% girls), consisting of 197 children with FHR-SZ (46.2% girls), 118 with FHR-BP (46.6% girls), and 199 controls (46.2% girls). Children with FHR-SZ were significantly impaired compared with controls on processing speed and working memory (Cohen d = 0.50; P < .001), executive and visuospatial functions (Cohen d = 0.28; P = .03), and declarative memory and attention (Cohen d = 0.29; P = .02). Compared with children with FHR-BP, children with FHR-SZ performed significantly poorer in processing speed and working memory (Cohen d = 0.40; P = .002), executive and visuospatial functions (Cohen d = 0.35; P = .008), and declarative memory and attention (Cohen d = 0.31; P = .03). Children with FHR-BP and controls did not differ.

CONCLUSIONS AND RELEVANCE

Children with FHR-SZ had widespread neurocognitive impairments, supporting the hypothesis of neurocognitive functions as endophenotypes of schizophrenia. The absence of neurocognitive deficits in children with FHR-BP suggests distinct neurodevelopmental manifestations in these familial high-risk groups at this age. Early detection of children with FHR-SZ and cognitive impairments is warranted to investigate associations of neurocognition with transition to psychosis, add to the knowledge of their developmental pathophysiology, and inform early intervention programs.

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.