Ole A Andreassen

Dados Biográficos

ID1751847
NOMEOle A Andreassen
PRENOMESOle A
SOBRENOMEAndreassen
ASSINATURAANDREASSEN O A
AFILIAÇÕESOslo University Hospital
ORCID0000-0002-4461-3568
VERIFICADOSim
TOTAL DE OBRAS34
TOTAL DE CITAÇÕES11
TOTAL COMO AUTOR34
TOTAL COMO EDITOR0
PRIMEIRO ANO DE PUBLICAÇÃO2014
ANO MAIS RECENTE DE PUBLICAÇÃO2026
ÍNDICE H2

  • Youth psychotic experiences

    Open AccessViktoria Birkenæs, Pravesh Parekh et al.ARTICLEJournal of Child Psychology and…2026

    BACKGROUND: Adolescent self-reported psychotic experiences are associated with mental illness and could help guide prevention strategies. Youth report substantially more experiences than adults. However, with large societal changes like the digital revolution and COVID-19 pandemic, existing questionnaires may no longer accurately capture youth experiences. We aimed to determine the ability of the CAPE-16 questionnaire in capturing psychotic exper…

  • Evocative effects of children's education‐associated genetics on maternal parenting

    Open AccessChloe Austerberry, Tetyana Zayats et al.ARTICLEJournal of Child Psychology and…2026

    Background It has long been hypothesized that increasing heritability with age of cognitive and educational performance is partly attributable to evocative gene–environment correlation. However, this hypothesis has not been widely tested. Methods We addressed this gap by examining whether children's education polygenic scores ( PGS edu ) were associated with maternal self‐reported positive and literacy‐focused parenting when children were 5 years…

  • Childhood trajectories of emotional and behavioral difficulties are related to polygenic liability for mood and anxiety disorders

    Open AccessNora R Bakken, N Parker et al.ARTICLEJournal of Child Psychology and…2025

    Background Symptoms related to mood and anxiety disorders (emotional disorders) often present in childhood and adolescence. Some of the genetic liability for mental disorders, and emotional and behavioral difficulties seems to be shared. Yet, it is unclear how genetic liability for emotional disorders and related traits influence trajectories of childhood behavioral and emotional difficulties, and if specific developmental patterns are associated…

  • The Genetics of Partnership Dissolution

    Open AccessRuth Eva Jørgensen, Rosa Cheesman et al.ARTICLESociological Science2025Citada por: 2

    There is a genetic component to divorce risk, but little is known about which and how genetically influenced traits are involved. This study makes three major contributions to address these gaps. First, we link genetic data from the Norwegian Mother, Father, and Child Cohort Study (MoBa) to population register data and estimate the total influence of common genetic variants on partnership dissolution (N = 121, 408). Then, we identify heritable tr…

  • Genome-wide association meta-analysis of age at onset of walking in over 70,000 infants of European ancestry

    Open AccessAiling Gui, Adam Hollowell et al.ARTICLENature Human Behaviour2025Referências: 126

    Age at onset of walking is an important early childhood milestone which is used clinically and in public health screening. In this genome-wide association study meta-analysis of age at onset of walking ( N = 70,560 European-ancestry infants), we identified 11 independent genome-wide significant loci. SNP-based heritability was 24.13% (95% confidence intervals = 21.86–26.40) with ~11,900 variants accounting for about 90% of it, suggesting high pol…

  • No evidence of positive causal effects of maternal and paternal age at first birth on children's test scores at age 10 years

    Open AccessMichael Grätz, Felix C Tropf et al.ARTICLENature Human Behaviour2025Referências: 24

    Research has shown that higher maternal and paternal age is positively associated with children's education. Debate continues as to whether these relationships are causal. This is of great interest given the postponement of first births in almost all developed countries during the twentieth century. Here we use an instrumental variable approach (Mendelian randomization) using maternal and paternal polygenic indices (PGIs) for age at first birth-w…

  • More than nature and nurture, indirect genetic effects on children's academic achievement are consequences of dynastic social processes

    Open AccessMichel G Nivard, Daniel W Belsky et al.ARTICLENature Human Behaviour2024Citada por: 6Referências: 39

  • Multivariate genetic analysis of personality and cognitive traits reveals abundant pleiotropy

    Open AccessGuy Hindley, Alexey A Shadrin et al.ARTICLENature Human Behaviour2023Referências: 75

    Personality and cognitive function are heritable mental traits whose genetic foundations may be distributed across interconnected brain functions. Previous studies have typically treated these complex mental traits as distinct constructs. We applied the 'pleiotropy-informed' multivariate omnibus statistical test to genome-wide association studies of 35 measures of neuroticism and cognitive function from the UK Biobank (n = 336,993). We identified…

  • Rare CNVs and phenome-wide profiling highlight brain structural divergence and phenotypical convergence

    Open AccessJakub Kopal, Kuldeep Kumar et al.ARTICLENature Human Behaviour2023Citada por: 1Referências: 72

  • Mapping genomic loci implicates genes and synaptic biology in schizophrenia

    Open AccessVassily Trubetskoy, Antonio F Pardiñas et al.ARTICLENature2022

  • Early manifestations of genetic risk for neurodevelopmental disorders

    Open AccessRagna Bugge Askeland, Laurie J Hannigan et al.ARTICLEJournal of Child Psychology and…2022

    BACKGROUND: Attention deficit/hyperactivity disorder (ADHD), autism spectrum disorder (autism) and schizophrenia are highly heritable neurodevelopmental disorders, affecting the lives of many individuals. It is important to increase our understanding of how the polygenic risk for neurodevelopmental disorders manifests during childhood in boys and girls. METHODS: Polygenic risk scores (PRS) for ADHD, autism and schizophrenia were calculated in a s…

  • How interactions between ADHD and schools affect educational achievement

    Open AccessRosa Cheesman, Espen M Eilertsen et al.ARTICLEJournal of Child Psychology and…2022

    BACKGROUND: Children with ADHD tend to achieve less than their peers in school. It is unknown whether schools moderate this association. Nonrandom selection of children into schools related to variations in their ADHD risk poses a methodological problem. METHODS: We linked data on ADHD symptoms of inattention and hyperactivity and parent-child ADHD polygenic scores (PGS) from the Norwegian Mother, Father, and Child Cohort Study (MoBa) to achievem…

  • On the importance of parenting in externalizing disorders

    Open AccessEspen M Eilertsen, Rosa Cheesman et al.ARTICLEJournal of Child Psychology and…2022

    BACKGROUND: Theoretical models of the development of childhood externalizing disorders emphasize the role of parents. Empirical studies have not been able to identify specific aspects of parental behaviors explaining a considerable proportion of the observed individual differences in externalizing problems. The problem is complicated by the contribution of genetic factors to externalizing problems, as parents provide both genes and environments t…

  • Preventive Medication Patterns in Bipolar Disorder and Their Relationship With Comorbid Substance Use Disorders in a Cross-National Observational Study

    Open AccessRomain Icick, Ingrid Melle et al.ARTICLEFrontiers in Psychiatry2022

    SUD comorbidity in BD was overall not associated with different pharmacological treatment in our sample, and not related to the level of compliance to guidelines. We found country-specific associations between comorbid SUDs and specific medications that warrant further studies

  • Study protocol for “MDMA-assisted therapy as a treatment for major depressive disorder

    Open AccessTor-Morten Kvam, Ivar W Goksøyr et al.ARTICLEFrontiers in Psychiatry2022

    EudraCT number 2021-000805-26

  • Lifetime Cannabis Use Is Not Associated With Negative Beliefs About Medication in Patients With First Treatment Psychosis

    Open AccessPriyanthi B Gjerde, Synne W Steen et al.ARTICLEFrontiers in Psychiatry2022

    Use of cannabis is not linked to negative perceptions about antipsychotic medicines in patients with FTP. Other reasons for poor compliance to antipsychotic drug treatment in cannabis users need to be further investigated

  • Negative Symptom Domains Are Associated With Verbal Learning in Adolescents With Early Onset Psychosis

    Open AccessLynn Mørch‐Johnsen, Lynn Mørch-Johnsen et al.ARTICLEFrontiers in Psychiatry2022

    Background: Early-onset psychosis (EOP) is among the leading causes of disease burden in adolescents. Negative symptoms and cognitive deficits predicts poorer functional outcome. A better understanding of the association between negative symptoms and cognitive impairment may inform theories on underlying mechanisms and elucidate targets for development of new treatments. Two domains of negative symptoms have been described in adult patients with …

  • Adiponectin Is Related to Cardiovascular Risk in Severe Mental Illness Independent of Antipsychotic Treatment

    Open AccessElina J Reponen, Martin Tesli et al.ARTICLEFrontiers in Psychiatry2021

    Background: Schizophrenia (SCZ) and bipolar disorder (BD) are severe mental illnesses (SMI) associated with elevated cardiovascular disease (CVD) risk, including obesity. Leptin and adiponectin are secreted by adipose tissue, with pro- and anti-inflammatory properties, respectively. The second generation antipsychotics (AP) olanzapine, clozapine, and quetiapine have been associated with high leptin levels in SMI. However, the link between inflamm…

  • Sex-Specific Effect of Serum Lipids and Body Mass Index on Psychotic Symptoms, a Cross-Sectional Study of First-Episode Psychosis Patients

    Open AccessPriyanthi B Gjerde, Carmen Simonsen et al.ARTICLEFrontiers in Psychiatry2021

    Background: Schizophrenia is a disorder with considerable heterogeneity in course and outcomes, which is in part related to the patients' sex. Studies report a link between serum lipids, body mass index (BMI), and therapeutic response. However, the role of sex in these relationships is poorly understood. In a cross-sectional sample of first-episode psychosis (FEP) patients, we investigated if the relationship between serum lipid levels (total cho…

  • Genetic loci shared between major depression and intelligence with mixed directions of effect

    Open AccessShahram Bahrami, Alexey A Shadrin et al.ARTICLENature Human Behaviour2021Referências: 45

  • Childhood Trauma in Persons With Schizophrenia and a History of Interpersonal Violence

    Open AccessGuttorm Breivik Storvestre, Arvid Jensen et al.ARTICLEFrontiers in Psychiatry2020

    SCZ-V patients had higher exposure to childhood trauma than SCZ-NV, and both schizophrenia groups had higher exposure than HC. The results suggest that childhood physical and emotional neglect may be of specific importance to later violence in schizophrenia

  • Childhood Trauma Is Nominally Associated With Elevated Cortisol Metabolism in Severe Mental Disorder

    Open AccessMonica Aas, Torill Ueland et al.ARTICLEFrontiers in Psychiatry2020

    Our study indicates that childhood physical abuse is associated with elevated cortisol metabolism (5β-reductase) in adults with a SZ or BD disorder. However, our study did not support cortisol metabolism as a mediator between childhood trauma experiences and cognitive function within these disorders

  • Insulin Resistance and Oxidative Stress

    Open AccessTao Qi, Qi Tao et al.ARTICLEFrontiers in Psychiatry2020

    Objective: The present study aimed to examine whether insulin resistance and oxidative stress are associated with cognitive impairment in first-episode drug-free schizophrenia (SZ) patients. Methods: Ninety first-episode SZ patients and 70 healthy controls were enrolled. Fasting insulin (FINS) and markers of oxidative stress [oxidized glutathione (GSSG), superoxide dismutase (SOD), nitric oxide (NO) and uric acid (UA) levels] were measured in ser…

  • Atherogenic Lipid Ratios Related to Myeloperoxidase and C-Reactive Protein Levels in Psychotic Disorders

    Open AccessElina J Reponen, Ingrid Dieset et al.ARTICLEFrontiers in Psychiatry2020

    Our findings suggest that low-grade inflammation and abnormal neutrophil activation may cause increased CVD risk in patients with psychotic disorders. These mechanisms should be further examined to determine the potential for development of novel risk evaluation strategies

  • Cannabis Use Is Associated With Increased Levels of Soluble gp130 in Schizophrenia but Not in Bipolar Disorder

    Open AccessAttila Szabó, Ibrahim A Akkouh et al.ARTICLEFrontiers in Psychiatry2020

    The complex effects of plant cannabinoids on human physiology is not yet fully understood, but include a wide spectrum of effects on immune modulation. The immune system and its inflammatory effector pathways are recently emerging as possible causative factors in psychotic disorders. The present study aimed to investigate whether self-administered Cannabis use was associated with changes in circulating immune and neuroendocrine markers in schizop…