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

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

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. 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. 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. 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

Impaired motor development in children with familial high risk of schizophrenia or bipolar disorder and the association with psychotic experiences: a 4-year Danish observational follow-up study.

Motor abnormalities have clinical relevance as a component of psychotic illness; they are not only a proxy of altered neurodevelopment, but also intimately related to psychotic risk. We aimed to assess motor development and its association with psychotic experiences in children with familial high risk (FHR) of schizophrenia or bipolar disorder compared with controls. The Danish High Risk and Resilience Study is a prospective longitudinal cohort study, for which participants were extracted from Danish registers. Children born in Denmark between Sept 1, 2004, and Aug 31, 2009, with no, one, or two parents born in Denmark with schizophrenia or bipolar disorder, could be included in the study. No ethnicity data were collected. Children with no biological parent diagnosed with schizophrenia spectrum disorder or bipolar disorder were matched to children with FHR of schizophrenia (one or two parents with schizophrenia spectrum disorder) on the basis of sex, age, and municipality. Children with FHR of bipolar disorder (one or two parents with bipolar disorder) were included as a non-matched group. We assessed motor function in children with FHR of schizophrenia, children with FHR of bipolar disorder, and children in the control group at approximately age 8 years (baseline; 2013-16) and age 12 years (follow-up; 2017-20) using the Movement Assessment Battery for Children-Second Edition (Movement ABC-2). Psychotic experiences were assessed using the psychosis section of the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version. Raters were masked regarding familial risk status. Motor development from baseline to follow-up in the different groups was assessed using a linear mixed model. Logistic regression examined the relationship between definite motor problems (≤5th percentile on Movement ABC-2) and psychotic experiences. Between March 1, 2017, and June 30, 2020, we studied 437 children (234 [54%] boys, 203 [46%] girls; mean age 11·99 years [SD 0·26, range 11·08-12·86]). Children with FHR of schizophrenia showed stable motor developmental deficits in manual dexterity (difference in intercept -1·62 [95% CI -2·39 to -0·85], p<0·0001; difference in slope 0·17 [-0·48 to 0·81], p=0·61) and balance (difference in intercept -1·58 [-2·34 to -0·82], p<0·0001; difference in slope 0·32 [-0·34 to 0·99], p=0·34), and a developmental lag in aiming and catching (difference in slope -1·07 [-1·72 to -0·41], p=0·0015; difference in intercept -0·59 [-1·35 to 0·17], p=0·13) compared with controls. Children with FHR of bipolar disorder showed no motor developmental differences on a group basis. Compared with controls, children with FHR of schizophrenia were more likely to have definite motor problems (odds ratio [OR] 2·86 [95% CI 1·60 to 5·11], p=0·0004), as were children with FHR of bipolar disorder (OR 2·45 [1·28 to 4·70], p=0·0068). Children with definite motor problems across all groups were more likely (OR 1·90 [1·12 to 3·21, p=0·017] to have had psychotic experiences than children with no definite motor problems. Clinicians should be aware that motor impairment in childhood can reflect neurodevelopmental vulnerability to psychosis. Our findings contribute to the identification of early risk markers for severe mental illness, both for use by clinicians and for establishing a basis for future primary preventive intervention studies in the premorbid phase. The Independent Research Fund Denmark, the Mental Health Services of the Capital Region of Denmark, the Lundbeck Foundation Initiative for Integrative Psychiatric Research (iPSYCH), Aarhus University, the Beatrice Surovell Haskell Fund, the Tryg Foundation, and the Innovation Fund Denmark. For the Danish translation of the abstract see Supplementary Materials section