Neuropsychological characteristics of child and adolescent offspring of patients with bipolar disorder

Brief Report: Intact Cognitive Functions in Children and Adolescents of Parents With Mood Disorders

OBJECTIVES

We aimed to identify if offspring of a parent with mood disorders presented cognitive deficits on 14 cognitive subtests while controlling for intellectual quotient, anxio-depressive symptoms, symptoms of attention deficit hyperactivity disorder (ADHD) or insomnia.

METHODS

Using the Healthy Brain Network biobank, we identified 44 offspring of a parent with bipolar disorder (BD), 87 offspring of a parent with major depressive disorder (MDD) and 88 offspring of healthy parents. Analyses of variance (ANOVA) were performed to determine if groups differed on 14 subtests of the Wechsler Intelligence Scale for Children-5th Edition (WISC) and National Institutes of Health toolbox.

RESULTS

Across all subtests, groups did not significantly differ. Only a subtle effect was found for male participants in which high-risk participants exhibited lower scores on the mental rotation subtest compared to the control group.

CONCLUSION

Overall, our results suggest intact cognition in young offspring of parents with a mood disorder.

Comparing cognition in parents with schizophrenia or bipolar disorder and their 7-year-old offspring

Individuals with schizophrenia (SZ) or bipolar disorder (BP) display cognitive impairments, while their first-degree relatives perform at an intermediate level between the patient groups and controls. However, the environmental impact of having an ill relative likely varies with the type of kinship and some studies suggest that offspring may be particularly disadvantaged. The present study aimed to investigate the relationship between parent and child cognition in parents with SZ or BD and their 7-year-old offspring. A population-based cohort of 522 children (parental SZ, n = 202; parental BP, n = 120; controls, n = 200) and their parents underwent the same assessment battery covering a wide range of cognitive functions. We used Bayesian statistics to model performance. We found that performance on non-verbal tests was better in offspring than parents with SZ or BP, using the controls as reference. However, for verbal tests, there was little to no evidence for this pattern or even some evidence for the opposite in the BP group: relatively better performance in parents than offspring. The findings suggest that the offspring of parents with SZ or BP may be particularly disadvantaged in verbal abilities. Future studies will show whether this pattern persists throughout development.

Comparison of the neurocognitive profile of the children of parents with bipolar disorder and controls: A transnational cross-sectional study

INTRODUCTION

Studies that have compared the cognitive alterations of the children of parents with bipolar disorder (CPBD) versus the children of control parents (CCP), present heterogeneous results due to the studies' methodological differences, the age of the population studied, and the lack of standardisation of the measures used for the different neurocognitive domains. The objective was to compare the neurocognitive profile of CPBD versus CCP to observe if there are differences that could be proposed as possible endophenotypes of BD.

RESULTS

A total of 107 individuals (51 CPBD, and 56 CCP) with ages between 6 and 16 (mean, 12.2±2.80) years of age were evaluated. Seventy-four point five percent of the CPBD group had some disorder compared to 67.9% of the CCP group. Tests such as letter-F phonemic verbal fluency, letter-S phonemic verbal fluency, overall F-A-S phonemic verbal fluency, story recall and retrieval, and Wisconsin perseverative errors showed a difference with a small effect size, but with a high degree of uncertainty.

CONCLUSIONS

The CPBD did not have differences in their neurocognitive profile in comparison with CCP. Both groups have a high prevalence of psychopathology, which is a factor that could explain the lack of differences in neurocognitive performance.

Child and adolescent anxiety as a risk factor for bipolar disorder: A systematic review of longitudinal studies

OBJECTIVES

Several studies have suggested that anxiety disorders in childhood and adolescence often precede the onset of bipolar disorder. We therefore systematically reviewed the relationship between child and adolescent anxiety and later bipolar disorder.

METHODS

Online databases (Medline [for Ovid], EMBASE and PsychINFO) were searched for original, peer-reviewed studies examining the relationship between child and adolescent anxiety and later bipolar disorder. Studies in both community samples and bipolar offspring samples were included.

RESULTS

A total of 16 studies were included in the review. The results were broadly consistent and revealed that child and adolescent anxiety disorders are associated with later bipolar disorder in community samples. In bipolar offspring, child and adolescent anxiety disorders are a marker of increased risk and predict the onset of bipolar disorder and other major mood disorders.

CONCLUSIONS

There is evidence that anxiety disorders in childhood and adolescence increase the risk of later bipolar disorder. Anxiety disorders may be a useful target for early intervention in those at high-risk of bipolar disorder.

Epigenetic age deacceleration in youth at familial risk for schizophrenia and bipolar disorder

Epigenetic modifications occur sequentially during the lifespan, but their pace can be altered by external stimuli. The onset of schizophrenia and bipolar disorder is critically modulated by stressors that may alter the epigenetic pattern, a putative signature marker of exposure to environmental risk factors. In this study, we estimated the age-related epigenetic modifications to assess the differences between young individuals at familial high risk (FHR) and controls and their association with environmental stressors. The sample included 117 individuals (6-17 years) at FHR (45%) and a control group (55%). Blood and saliva samples were used estimate the epigenetic age with six epigenetic clocks through methylation data. Environmental risk was measured with obstetric complications, socioeconomic statuses and recent stressful life events data. Epigenetic age was correlated with chronological age. FHR individuals showed epigenetic age deacceleration of Horvath and Hannum epigenetic clocks compared to controls. No effect of the environmental risk factors on the epigenetic age acceleration could be detected. Epigenetic age acceleration adjusted by cell counts showed that the FHR group was deaccelerated also with the PedBE epigenetic clock. Epigenetic age asynchronicities were found in the young at high risk, suggesting that offspring of affected parents follow a slower pace of biological aging than the control group. It still remains unclear which environmental stressors orchestrate the changes in the methylation pattern. Further studies are needed to better characterize the molecular impact of environmental stressors before illness onset, which could be critical in the development of tools for personalized psychiatry.

Academic performance in adolescent offspring of mothers with prenatal and perinatal psychiatric hospitalizations: A register-based, data linkage, cohort study

BACKGROUND

This is the first study to investigate the longitudinal association between prenatal and perinatal psychiatric hospitalizations and academic achievements in adolescent offspring.

METHODS

We conducted an administrative health data-based cohort study of 168, 528 mother-offspring pairs using linked data obtained from health and educational registries in New South Wales, Australia. Prenatal and perinatal maternal psychiatric diagnosis was measured by using ICD-10. The National Assessment Program for Literacy and Numeracy (NAPLAN) was used to assess the educational performance of the offspring. Logistic regression model was used to explore the association. Multivariate models were adjusted for maternal sociodemographic characteristics such as age at birth, marital status, educational status, and occupational status, maternal diabetes and chronic hypertension, maternal smoking during pregnancy, birth weight, and language spoken at home.

RESULTS

The findings show that after adjusting for important covariates adolescent offspring of mothers with prenatal and perinatal psychiatric hospitalizations were more likely to perform below the national minimum standard in all domains of academic performance at age 14 years, when compared with the offspring of mothers without such hospitalizations, with the highest odds for numeracy (OR = 2.88; 95% CI: 2.50-3.31) followed by reading (OR = 2.08; 95% CI: 1.81-2.38), spelling (OR = 1.74; 95% CI: 1.51-2.01), and writing (OR = 1.56; 95% CI: 1.34-1.80). There was significant gender interaction such that males were more likely to experience lower rates of academic performance than females in all academic domains. Lower academic achievements were observed among offspring of mothers with all major groupings of psychiatric disorders, with a higher risk for severe psychiatric disorders followed by mental disorders due to substance use or medical conditions.

CONCLUSION

In sum, maternal prenatal and perinatal psychiatric hospitalizations are associated with lower academic achievements in adolescent offspring, with a stronger effect on the academic performance of male offspring. Early intervention strategies that aim to enhance educational performance in the exposed offspring are needed.

Aging in bipolar disorder: Cognitive performance and clinical factors based on an adulthood-lifespan perspective

BACKGROUND

The evolution of cognitive performance throughout the lifespan in bipolar disorder (BD) is understudied. This cross-sectional study aims to describe the cognitive performance across age groups.

METHODS

A sample of 654 participants was recruited for this study (BD = 432 and healthy controls -HC- =222). Three subgroups, divided according to age range (18 to 35, 36 to 49, and ≥50 years old) were analyzed after administering a comprehensive neuropsychological battery including six cognitive domains. Demographic, clinical, and psychosocial functioning data were also analyzed. Generalized linear models (GLM) with age, diagnostic group, and age × group as main effects were carried out to examine their potential association on cognitive domains. Subsequently, a GLM in the BD sample was conducted to analyze interactions of several clinical variables by age on each cognitive domain.

RESULTS

Main effects of diagnostic group and age were found in all cognitive domains. Significant group × age effect interaction was found for attention domain (p = 0.02) demonstrating a worse cognitive evolution across age in BD, driven by older age, but not in HC. Significant interaction effects of higher number of manic episodes and older age were also found in attention and verbal memory. Older age was also associated with a longer duration of illness, higher number of episodes, more somatic comorbidities, and poorer psychosocial functioning.

CONCLUSIONS

These results suggest that older age was associated with a selective cognitive decline in BD in the attentional domain. These findings highlight the importance of developing interventions targeting cognitive dysfunction throughout the BD adulthood lifespan.

Transmission of intelligence, working memory, and processing speed from parents to their seven-year-old offspring is function specific in families with schizophrenia or bipolar disorder

BACKGROUND

Prior studies have shown high heritability estimates regarding within-function transmission of neurocognition, both in healthy families and in families with schizophrenia but it remains an open question whether transmission from parents to offspring is function specific and whether the pattern is the same in healthy families and families with schizophrenia or bipolar disorder. We aimed to characterize the transmission of intelligence, processing speed, and verbal working memory functions from both biological parents to their 7-year-old offspring in families with parental schizophrenia, bipolar disorder, and population-based control parents.

METHODS

The population-based cohort consists of 7-year-old children with one parent diagnosed with schizophrenia (n = 186), bipolar disorder (n = 114), and of parents without schizophrenia or bipolar disorder (n = 192). Children and both parents were assessed using identical, age-relevant neurocognitive tests of intelligence, verbal working memory, and processing speed.

RESULTS

In multiple regression analyses children's intelligence, verbal working memory, and processing speed scores were significantly associated with the corresponding parental cognitive function score. All associations from parents to offspring across functions were non-significant. No significant parental cognitive function by group interaction was observed.

CONCLUSION

Transmissions of intelligence, processing speed, and verbal working memory from parents to offspring are function specific. The structure of transmission is comparable between families with schizophrenia, families with bipolar disorder and families without these disorders.

Neurocognitive Development in Children at Familial High Risk of Schizophrenia or Bipolar Disorder

IMPORTANCE

Neurocognitive impairments exist in children at familial high risk (FHR) of schizophrenia and bipolar disorder. Studies on preadolescent developmental courses of neurocognition are important to describe shared and distinct neurodevelopmental pathways in these groups.

OBJECTIVE

To assess the development in specific neurocognitive functions from age 7 to 11 years in children at FHR of schizophrenia or bipolar disorder compared with children in a population-based control (PBC) group.

DESIGN, SETTING, AND PARTICIPANTS

The Danish High Risk and Resilience Study is a prospective, longitudinal, cohort study that collected data from January 1, 2013, to January 31, 2016 (phase 1), and from March 1, 2017, to June 30, 2020 (phase 2). Data were collected at 2 university hospitals in Denmark, and participants included 520 children at FHR of schizophrenia or bipolar disorder along with a PBC group matched with the group of children at FHR of schizophrenia by age, sex, and municipality.

EXPOSURES

Parental schizophrenia, bipolar disorder, or neither.

MAIN OUTCOMES AND MEASURES

Neurocognitive functioning was assessed with validated tests of intelligence, processing speed, attention, memory, verbal fluency, and executive functioning. Multilevel mixed-effects linear regression models with maximum likelihood estimation were used to estimate neurocognitive development from age 7 to 11 years.

RESULTS

At 4-year follow-up, a total of 451 children (mean [SD] age; 11.9 [0.2] years; 208 girls [46.1%]) underwent neurocognitive testing. There were a total of 170 children at FHR of schizophrenia (mean [SD] age, 12.0 [0.3]; 81 girls [47.7%]), 103 children at FHR of bipolar disorder (mean [SD] age, 11.9 [0.2] years; 45 girls [43.7%]), and 178 children in the PBC group (mean [SD] age, 11.9 [0.2] years; 82 girls [46.1%]). At either age 7 or 11 years or at both assessments, 520 children participated in the neurocognitive assessment and were therefore included in the analyses. When correcting for multiple comparisons, no statistically significant time × group interactions were observed across the 3 groups. Compared with the PBC group at 4-year follow-up, children at FHR of schizophrenia showed significant neurocognitive impairment in 7 of 24 neurocognitive measures (29.2%; Cohen d range, 0.29-0.37). Compared with children at FHR of bipolar disorder, children at FHR of schizophrenia had significant neurocognitive impairment in 5 of 24 measures (20.8%; Cohen d range, 0.29-0.38). Children at FHR of bipolar disorder and those in the PBC group did not differ significantly.

CONCLUSIONS AND RELEVANCE

In this cohort study, findings suggest that neurocognitive maturation was comparable across groups of children at FHR of schizophrenia or bipolar disorder compared with PBCs from age 7 to 11 years. Compared with the PBC group, children at FHR of schizophrenia demonstrated widespread, stable, neurocognitive impairments during this period, whereas children at FHR of bipolar disorder showed no neurocognitive impairments, which may indicate distinct neurodevelopmental pathways in children at FHR of schizophrenia and bipolar disorder.

Cognitive Remediation in Psychiatric Disorders: State of the Evidence, Future Perspectives, and Some Bold Ideas

Many people with psychiatric disorders experience impairments in cognition. These deficits have a significant impact on daily functioning and sometimes even on the further course of their disease. Cognitive remediation (CR) is used as an umbrella term for behavioral training interventions to ameliorate these deficits. In most but not all studies, CR has proven effective in improving cognition and enhancing everyday functional outcomes. In this paper, after quickly summarizing the empirical evidence, practical advice to optimize the effects of CR interventions is provided. We advocate that CR interventions should be as fun and motivating as possible, and therapists should at least consider using positively toned emotional stimuli instead of neutral stimuli. Participants should be screened for basic processing deficits, which should be trained before CR of higher-order cognitive domains. CR should stimulate metacognition and utilize natural settings to invoke social cognition. Wherever possible, CR tasks should link to tasks that participants face in their everyday life. Therapists should consider that participants might also benefit from positive side effects on symptomatology. Finally, the CR approach might even be utilized in settings where the treatment of cognitive impairments is not a primary target.

The effect of prenatal lithium exposure on the neuropsychological development of the child

OBJECTIVES

Lithium is an effective treatment for bipolar disorder, also during pregnancy to prevent the recurrence of episodes in the perinatal period. Little is known about the neuropsychological development of lithium-exposed offspring. The current study was designed to investigate neuropsychological functioning in lithium-exposed children with the aim to provide further knowledge on the long-term effects of lithium use during pregnancy.

METHODS

Participants were offspring of women with a diagnosis of bipolar spectrum disorder, aged 6-14 years. In total, 99 children participated in the study, 56 were exposed to lithium in utero and 43 were not exposed to lithium. Neuropsychological tests were administered, including the Snijders-Oomen Nonverbal Intelligence Test and the NEPSY-II-NL assessment. Linear and negative binomial regression models were used to investigate the association between prenatal lithium exposure and neuropsychological functioning. In secondary analyses, the association between lithium blood level during pregnancy and neuropsychological functioning was assessed. Additionally, norm scores and percentiles for task outcomes were calculated.

RESULTS

Lithium use during pregnancy was associated with the total number of mistakes made on the Auditory Attention task, but not statistically significant after full adjustment for potential confounding factors. No association between prenatal lithium exposure and IQ was found. Also, no relationship between lithium blood level during pregnancy and neuropsychological functioning was found after adjustment for potential confounders. Task outcomes in both groups were comparable to the general population.

CONCLUSION

In this study, we found no evidence for significantly altered neuropsychological functioning of lithium-exposed children at the age of 6-14 years, when compared to non-lithium-exposed controls.

Cognitive reserve and its correlates in child and adolescent offspring of patients diagnosed with schizophrenia or bipolar disorder

AIM

To analyze cognitive reserve (CR) in child and adolescent offspring of patients diagnosed with schizophrenia (SZ-off) or bipolar disorder (BD-off) and compare them with a group of community controls (CC-off). We also aimed to investigate whether there was an association between CR and clinical and neuropsychological variables according to group.

METHODS

The study included 46 SZ-off, 105 BD-off and 102 CC-off. All participants completed assessments regarding CR and clinical, neuropsychological and psychosocial functioning. CR was measured with a proxy based on premorbid intelligence, parental occupational level, educational attainment, developmental milestones and sociability. The clinical assessment included the Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime, the Semi-structured Interview for Prodromal Syndromes, and the Global Assessment Functioning scale. The neuropsychological assessment included measures of executive functioning, attention, verbal memory, working memory and processing speed.

RESULTS

SZ-off showed a lower level of CR compared to BD-off and CC-off, while BD-off showed an intermediate level of CR between SZ-off and CC-off. Moreover, an association between higher CR and less lifetime psychopathology, fewer prodromal psychotic symptoms, higher psychosocial functioning, and a higher working memory score was observed in all groups, but it was stronger in SZ-off.

CONCLUSIONS

CR seemed to be associated with psychopathology, clinical symptoms, psychosocial functioning, and some cognitive functions. SZ-off appeared to benefit more from a higher CR, therefore it could be considered a protective factor against the development of clinical symptomatology and cognitive impairment.

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.

Comparison of the Neurocognitive Profile of the Children of Parents with Bipolar Disorder and Controls: a Transnational Cross-Sectional Study

INTRODUCTION

Studies that have compared the cognitive alterations of the children of parents with bipolar disorder (CPBD) versus the children of control parents (CCP), present heterogeneous results due to the studies' methodological differences, the age of the population studied, and the lack of standardisation of the measures used for the different neurocognitive domains. The objective was to compare the neurocognitive profile of CPBD versus CCP to observe if there are differences that could be proposed as possible endophenotypes of BD.

RESULTS

A total of 107 individuals (51 CPBD, and 56 CCP) with ages between 6 and 16 (mean, 12.2±2.80) years of age were evaluated. Seventy-four point five percent of the CPBD group had some disorder compared to 67.9% of the CCP group. Tests such as letter-F phonemic verbal fluency, letter-S phonemic verbal fluency, overall F-A-S phonemic verbal fluency, story recall and retrieval, and Wisconsin perseverative errors showed a difference with a small effect size, but with a high degree of uncertainty.

CONCLUSIONS

The CPBD did not have differences in their neurocognitive profile in comparison with CCP. Both groups have a high prevalence of psychopathology, which is a factor that could explain the lack of differences in neurocognitive performance.

Cognitive heterogeneity in the offspring of patients with schizophrenia or bipolar disorder: a cluster analysis across family risk

BACKGROUND

Neurocognitive impairment is considered to lie on a continuum of severity across schizophrenia (SZ) and bipolar disorder (BP), possibly reflecting a gradient of neurodevelopmental load. Cluster analyses have identified different levels of impairment across the two disorders, from none to widespread and severe. We for the first time used this approach to examine cognitive function pooling together children and adolescents at familial risk of SZ or BP.

METHODS

220 participants, 49 offspring of individuals with schizophrenia (SZO), 90 offspring of individuals with bipolar disorder (BPO) and 81 offspring of healthy control parents (HC), aged 6 to 17 years, underwent a comprehensive clinical and cognitive assessment. Cognitive measures were used to group SZO and BPO using K-means clustering. Cognitive performance within each of the clusters was compared to that of HC and clinical variables were compared between clusters.

RESULTS

We identified three cognitive subgroups: a moderate impairment group, a mild impairment group, and a cognitively intact group. Both SZO and BPO were represented in each of the clusters, yet not evenly, with a larger proportion of the SZO in the moderately impaired cluster, but also a subgroup of BPO showing moderate cognitive dysfunction.

LIMITATIONS

Participants have yet to reach the age of onset for the examined disorders.

CONCLUSIONS

The findings point to a range of neurodevelopmental loadings across youth at familial risk of both SZ and BP. They have therefore important implications for the stratification of cognitive functioning and the possibility to tailor interventions to individual levels of impairment.

The Dutch Bipolar Offspring Study: Cognitive Development and Psychopathology

Various aspects of the relationship between cognitive impairment and bipolar disorder are not clear yet. This study examines cognitive and educational functioning prospectively in offspring at familial risk for bipolar disorder, in order to improve our understanding of the association between cognitive functioning and psychopathology. Bipolar offspring (N = 92) from the prospective Dutch bipolar offspring study were evaluated at adolescence and adulthood for IQ estimate, educational achievement and development of any psychiatric disorder. The main outcome was IQ estimate after 12 years of follow-up (offspring mean age 28 years). Generalized estimating equation (GEE) analyses showed that any lifetime DSM-IV axis I diagnosis was related to a lower cognitive outcome at adulthood as compared to unaffected bipolar offspring. No specific association was found for type of diagnosis. Early onset psychopathology (diagnosis at or before age 15 years) was significantly related to lower IQ estimate at adulthood, indicating a sensitive period for neurocognitive development.

Neuropsychological, clinical and environmental predictors of severe mental disorders in offspring of patients with schizophrenia

Offspring of individuals with schizophrenia (SZCOff) are at an increased risk for this disorder. Neuropsychological decline is a core feature of the disorder and researchers have reported increasing impairments in cognition during the prodromal phase in high-risk adolescents. Additionally, factors like the presence of prodromal symptoms or specific behavioral patterns could predict, together with neurocognitive functioning, the risk of conversion to severe mental disorders in SCZOff. This study aims to compare the neuropsychological functioning of a sample of 41 SCZOff children and adolescents and 105 community control offspring (CCOff) and to develop a prediction model to examine whether neuropsychological functioning, clinical and behavioral factors predict subsequent risk of severe mental disorders. We collected demographic, clinical and neuropsychological data. We found significant differences between groups in working memory, speed of processing, verbal memory and learning, visual memory and intelligence quotient (IQ). The socioeconomic status, verbal memory, working memory and positive prodromal symptoms predicted a significant proportion of the dependent variable variance. In conclusion, SCZOff showed neurocognitive impairments in several neuropsychological domains compared to CCOff. Neuropsychological functioning, environmental factors and positive prodromal symptoms could predict the risk of onset of severe mental disorders in SCZOff.

A meta-analysis of neurocognition in youth with familial high risk for bipolar disorder

Objective:

Neuropsychological impairment, including deficits in social cognition is evident in subjects at genetic high-risk for psychosis. However, findings in youth at genetic risk to bipolar disorder (BP) have been suggested to be less supportive of premorbid deficits. We aimed to conduct a meta-analysis of cognitive deficits in youth with familiar risk for bipolar disorder (FHR-BD).

Methods:

A novel meta-analysis of FHR-BD (mean age 10–25), including 18 studies (786 offsprings/siblings of patients with BD and 794 healthy controls), was conducted.

Results:

Both general cognition (d = 0.29, CI = 0.15–0.44) and social cognition (d = 0.23, CI = 0–0.45) were impaired in FHR-BD. In comparison to controls, FHR-BD had significant deficits in several cognitive domains, including visual memory (d = 0.35), verbal memory (d = 0.21), processing speed (d = 0.26) and sustained attention (d = 0.36). There was no significant difference between FHR-BD and controls in planning and working memory.

Conclusions:

Cognitive deficits are evident in individuals who are at genetic high-risk for developing BD. Neurodevelopmental abnormalities are likely playing a role not only in schizophrenia but also in BD.

Neurocognition in young offspring of individuals with bipolar disorder: The role of co-existing familial and clinical high-risk for bipolar disorder

Bipolar disorder (BD) is associated with cognitive dysfunction which has also been reported in offspring of individuals with BD (BDoff). However, it remains unclear whether cognitive underperformance in BDoff is associated with the presence of history of subclinical syndromes associated with risk for BD. To address this knowledge gap we assessed executive function, visual and verbal memory, working memory, processing speed and verbal fluency in 21 offspring with clinical high risk (CHR; BDoff+CHR), 54 offspring without CHR (BDoff-non-CHR), and 50 healthy individuals without familial risk of BD. BDoff underperformed compared to controls in most cognitive tasks. There was no significant neurocognitive difference between BDoff+CHR and BDoff-non-CHR except in the fluency/central executive domain (Cohen's d = 0.60, p = 0.03). Our results suggest that cognitive dysfunction in multiple domains is associated with familial predisposition to BD regardless of CHR status. On the other hand, abnormalities in central executive processes might be more pronounced in BDoff+CHR than BDoff-non-CHR. Further longitudinal studies investigating cognitive trajectory of BDoff and its interaction with the emergence of subclinical syndromes are needed to fully characterize the relationship between cognition and mood dysregulation in BD.

Neurocognitive heterogeneity in young offspring of patients with bipolar disorder: The effect of putative clinical stages

BACKGROUND

Bipolar disorder (BD) is associated with significant cognitive heterogeneity. In recent years, a number of studies have investigated cognitive subgroups in BD using data-driven methods and found that BD includes several subgroups including a severely impaired and a neurocognitively intact cluster. Studies in offspring of BD (BDoff) are particularly important to establish the timing of emergence of cognitive subgroups but studies investigating cognitive heterogeneity in BDoff are lacking. Our aim was to investigate cognitive heterogeneity in BDoff and the relationship between cognitive heterogeneity and putative clinical stages of BD.

METHODS

Seventy-one euthymic BDoff and 50 healthy controls were assessed using clinical measures and a battery of neuropsychological tests. Neurocognitive subgroups were investigated using latent class analysis.

RESULTS

Three neurocognitive subgroups, including a severe impairment group, a good performance cluster, and a subgroup characterized by intermediate/selective impairment was found. Both severe and intermediate level impairment subgroups underperformed healthy controls in processing speed, verbal fluency, visual memory and working memory. Deficits in verbal memory and executive functions were only evident in severe impairment subgroup. The putative stage of the illness had no significant effect on cognitive clustering of BDoff. Trait impulsivity scores were significantly increased in severe and intermediate impairment clusters but not in the cognitively good functioning subgroup of BDoff.

LIMITATIONS

The cross-sectional nature of the study was the main consideration.

CONCLUSION

These results suggest that cognitive heterogeneity is premorbid characteristic of BD and cognitive subgroups of BDoff emerge prior to the onset of illness and prodromal symptoms.

Neuropsychological Functioning and Temperament Traits in a Czech Sample of Children and Adolescents at Familial Risk of Bipolar Disorder

Background: Although a positive family history is the strongest predictor for bipolar disorder (BD), most offspring of BD parents (BO) will not develop the disorder. Identification of vulnerability markers for BD is essential for specific individual risk estimation. Impairments in cognitive functioning and the presence of specific temperament traits are considered promising candidates. Methods: Sixty-three BO (48% female; 11.8 ± 3.3 years) and 54 control offspring (CO; 44% female; 12.3 ± 3.2 years) comparable in sex (p = 0.4) and age (p = 0.4) were enrolled. Detection of current sub/threshold mood symptoms by the Kiddie Schedule for Affective Disorders and Schizophrenia and General Behavior Inventory was applied to separate BO into ultrahigh-risk (UHR) and high-risk (HR) subgroups. Cognitive functions were tested by the Developmental Neuropsychological Assessment II test battery, d2 Test of Attention, and Amsterdam Neuropsychological Tasks. Temperament was assessed by the Temperament in Middle Childhood and Early Adolescent Temperament Questionnaires. Results: The BO sample consisted of 5 BD, 17 UHR, and 41 HR participants. We did not observe any significant differences between the BO and CO groups or between the UHR, HR, and CO subgroups (Hedges' g = 0.21-0.39) in cognitive functioning. The BO differed significantly in some temperament traits from the CO (g = 0.42-0.61), while the UHR subgroup exhibited lower effortful control and attention focusing than both HR and CO participants (g = 0.92-1.19). Limitations: The cross-sectional design and wide age range of the sample limited our findings. Conclusions: Neuropsychological impairment does not seem to be a trait marker of BD in the premorbid stage. Temperament with low effortful control and low attention focusing might be associated with the development of mood disorders in BO.

Jepsen JR, Siebner HR, Østergaard L, Bliksted VF, Plessen KJ, Mors O, Nordentoft M. 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.

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.

Offspring of parents with mood disorders: time for more transgenerational research, screening and preventive intervention for this high-risk population

PURPOSE OF REVIEW

Offspring of parents with mood disorders (major depressive and bipolar disorder) are at increased risk for developing mood disorders. In this review, an overview regarding the intergenerational transmission of mood disorders, screening, and preventive intervention is given for this vulnerable group.

RECENT FINDINGS

Offspring of parents with depression have a 40% chance of developing a depression, whereas offspring of parents with bipolar disorder have a 10% chance of developing a bipolar disorder by adulthood. Studies into the intergenerational transmission of mood disorders show that children of parents with mood disorders have increased biological dysregulation and neuropsychosocial impairments. Although there is a clear need for early identification of those at the highest risk, there are few systematic attempts in mental health care to screen children of parents with mood disorders. Lastly, preventive interventions seem to be effective in reducing depressive symptoms of children of parents with depression; however, those effects are small and short-lived.

SUMMARY

Offspring of parents with mood disorders constitute a vulnerable group at high risk of mood disorders. More research needs to be conducted regarding mechanisms of the intergenerational transmission. Moreover, screening and preventive interventions for these offspring should be systematically evaluated and implemented.

Cognitive Impairment in Bipolar Disorder: Treatment and Prevention Strategies

Over the last decade, there has been a growing appreciation of the importance of identifying and treating cognitive impairment associated with bipolar disorder, since it persists in remission periods. Evidence indicates that neurocognitive dysfunction may significantly influence patients' psychosocial outcomes. An ever-increasing body of research seeks to achieve a better understanding of potential moderators contributing to cognitive impairment in bipolar disorder in order to develop prevention strategies and effective treatments. This review provides an overview of the available data from studies examining treatments for cognitive dysfunction in bipolar disorder as well as potential novel treatments, from both pharmacological and psychological perspectives. All these data encourage the development of further studies to find effective strategies to prevent and treat cognitive impairment associated with bipolar disorder. These efforts may ultimately lead to an improvement of psychosocial functioning in these patients.

Neuropsychological characteristics of child and adolescent offspring of patients with schizophrenia or bipolar disorder

BACKGROUND

Schizophrenia (SZ) and bipolar disorder (BD) are considered neurobiological disorders which share some clinical, cognitive and neuroimaging characteristics. Studying child and adolescent offspring of patients diagnosed with bipolar disorder (BDoff) or schizophrenia (SZoff) is regarded as a reliable method for investigating early alterations and vulnerability factors for these disorders. This study compares the neuropsychological characteristics of SZoff, BDoff and a community control offspring group (CC) with the aim of examining shared and differential cognitive characteristics among groups.

METHODS

41 SZoff, 90 BDoff and 107 CC were recruited. They were all assessed with a complete neuropsychological battery which included intelligence quotient, working memory (WM), processing speed, verbal memory and learning, visual memory, executive functions and sustained attention.

RESULTS

SZoff and BDoff showed worse performance in some cognitive areas compared with CC. Some of these difficulties (visual memory) were common to both offspring groups, whereas others, such as verbal learning and WM in SZoff or PSI in BDoff, were group-specific.

CONCLUSIONS

The cognitive difficulties in visual memory shown by both the SZoff and BDoff groups might point to a common endophenotype in the two disorders. Difficulties in other cognitive functions would be specific depending on the family diagnosis.

Neuropsychological study of IQ scores in offspring of parents with bipolar I disorder

INTRODUCTION

Studies comparing IQ in Offspring of Bipolar Parents (OBP) with Offspring of Healthy Controls (OHC) have reported conflicting findings. They have included OBP with mental health/neurodevelopmental disorders and/or pharmacological treatment which could affect results. This UK study aimed to assess IQ in OBP with no mental health/neurodevelopmental disorder and assess the relationship of sociodemographic variables with IQ.

METHODS

IQ data using the Wechsler Abbreviated Scale of Intelligence (WASI) from 24 OBP and 34 OHC from the North East of England was analysed using mixed-effects modelling.

RESULTS

All participants had IQ in the average range. OBP differed statistically significantly from OHC on Full Scale IQ (p = .001), Performance IQ (PIQ) (p = .003) and Verbal IQ (VIQ) (p = .001) but not on the PIQ-VIQ split. OBP and OHC groups did not differ on socio-economic status (SES) and gender. SES made a statistically significant contribution to the variance of IQ scores (p = .001).

CONCLUSIONS

Using a robust statistical model of analysis, the OBP with no current/past history of mental health/neurodevelopmental disorders had lower IQ scores compared to OHC. This finding should be borne in mind when assessing and recommending interventions for OBP.

Neurobiology of Risk for Bipolar Disorder

Bipolar disorder (BD) is a chronic mental illness which follows a relapsing and remitting course and requires lifetime treatment. The lack of biological markers for BD is a major difficulty in clinical practice. Exploring multiple endophenotypes to fit in multivariate genetic models for BD is an important element in the process of finding tools to facilitate early diagnosis, early intervention, prevention of new episodes, and follow-up of treatment response in BD. Reviewing of studies on neuroimaging, neurocognition, and biochemical parameters in populations with high genetic risk for the illness can yield an integrative perspective on the neurobiology of risk for BD. The most up-to-date data reveals consistent deficits in executive function, response inhibition, verbal memory/learning, verbal fluency, and processing speed in risk groups for BD. Functional magnetic resonance imaging (fMRI) studies report alterations in the activity of the inferior frontal gyrus, medial prefrontal cortex, and limbic areas, particularly in the amygdala in unaffected first-degree relatives (FDR) of BD compared to healthy controls. Risk groups for BD also present altered immune and neurochemical modulation. Despite inconsistencies, accumulating data reveals cognitive and imaging markers for risk and to a less extent resilience of BD. Findings on neural modulation markers are preliminary and require further studies. Although the knowledge on the neurobiology of risk for BD has been inadequate to provide benefits for clinical practice, further studies on structural and functional changes in the brain, neurocognitive functioning, and neurochemical modulation have a potential to reveal biomarkers for risk and resilience for BD. Multimodal, multicenter, population-based studies with large sample size allowing for homogeneous subgroup analyses will immensely contribute to the elucidation of biological markers for risk for BD in an integrative model.