This study aimed to compare the psychopathological profiles of children at familial high risk of schizophrenia spectrum psychosis (FHR-SZ) or bipolar disorder (FHR-BP) with population-based controls. We used Danish nationwide registers to retrieve a cohort of 522 seven-year-old children of parents with schizophrenia spectrum psychosis (N=202), bipolar disorder (N=120) or none of these disorders (N=200). Psychopathology was assessed by reports from multiple informants, including children, parents and teachers. Lifetime DSM-IV diagnoses were ascertained by blinded raters through the Schedule for Affective Disorders and Schizophrenia for School-Age Children. The dimensional assessment of psychopathology was performed by the Child Behavior Checklist, the Teacher's Report Form, a modified version of the ADHD-Rating Scale, the Test Observation Form, and the State-Trait Anxiety Inventory for Children. Current level of functioning was evaluated using the Children's Global Assessment Scale (CGAS). The prevalence of lifetime psychiatric diagnoses was significantly higher in both FHR-SZ children (38.7%, odds ratio, OR=3.5, 95% confidence interval, CI: 2.2-5.7, p < 0.001) and FHR-BP children (35.6%, OR=3.1, 95% CI: 1.8-5.3, p < 0.001) compared with controls (15.2%). FHR-SZ children displayed significantly more dimensional psychopathology on all scales and subscales compared with controls except for the Anxious subscale of the Test Observation Form. FHR-BP children showed higher levels of dimensional psychopathology on several scales and subscales compared with controls, but lower levels compared with FHR-SZ children. Level of functioning was lower in both FHR-SZ children (CGAS mean score = 68.2; 95% CI: 66.3-70.2, p < 0.0001) and FHR-BP children (73.7; 95% CI: 71.2-76.3, p < 0.05) compared with controls (77.9; 95% CI: 75.9-79.9). In conclusion, already at the age of seven, FHR-SZ and FHR-BP children show a higher prevalence of a broad spectrum of categorical and dimensional psychopathology compared with controls. These results emphasize the need for developing early intervention strategies towards this vulnerable group of children.

BackgroundSevere 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/designWe are establishing a cohort of 520 7-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.DiscussionData 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.