@article{BaaderKianiBrunkhorstKanaanetal.2020,
  author    = {Baader, Anna and Kiani, Behnaz and Brunkhorst-Kanaan, Nathalie and Kittel-Schneider, Sarah and Reif, Andreas and Grimm, Oliver},
  title     = {A within-sample comparison of two innovative neuropsychological tests for assessing ADHD},
  series = {Brain Sciences},
  volume    = {11},
  journal   = {Brain Sciences},
  number    = {1},
  issn      = {2076-3425},
  doi       = {10.3390/brainsci11010036},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220089},
  year      = {2020},
  abstract  = {New innovative neuropsychological tests in attention deficit hyperactivity disorder ADHD have been proposed as objective measures for diagnosis and therapy. The current study aims to investigate two different commercial continuous performance tests (CPT) in a head-to-head comparison regarding their comparability and their link with clinical parameters. The CPTs were evaluated in a clinical sample of 29 adult patients presenting in an ADHD outpatient clinic. Correlational analyses were performed between neuropsychological data, clinical rating scales, and a personality-based measure. Though inattention was found to positively correlate between the two tests (r = 0.49, p = 0.01), no association with clinical measures and inattention was found for both tests. While hyperactivity did not correlate between both tests, current ADHD symptoms were positively associated with Nesplora Aquarium's motor activity (r = 0.52 to 0.61, p < 0.05) and the Qb-Test's hyperactivity (r = 0.52 to 0.71, p < 0.05). Conclusively, the overall comparability of the tests was limited and correlation with clinical parameters was low. While our study shows some interesting correlation between clinical symptoms and sub-scales of these tests, usage in clinical practice is not recommended.},
  language  = {en}
}
@article{BiereKranzMaturaetal.2020,
  author    = {Biere, Silvia and Kranz, Thorsten M. and Matura, Silke and Petrova, Kristiyana and Streit, Fabian and Chiocchetti, Andreas G. and Grimm, Oliver and Brum, Murielle and Brunkhorst-Kanaan, Natalie and Oertel, Viola and Malyshau, Aliaksandr and Pfennig, Andrea and Bauer, Michael and Schulze, Thomas G. and Kittel-Schneider, Sarah and Reif, Andreas},
  title     = {Risk Stratification for Bipolar Disorder Using Polygenic Risk Scores Among Young High-Risk Adults},
  series = {Frontiers in Psychiatry},
  volume    = {11},
  journal   = {Frontiers in Psychiatry},
  doi       = {10.3389/fpsyt.2020.552532},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-214976},
  year      = {2020},
  abstract  = {Objective: Identifying high-risk groups with an increased genetic liability for bipolar disorder (BD) will provide insights into the etiology of BD and contribute to early detection of BD. We used the BD polygenic risk score (PRS) derived from BD genome-wide association studies (GWAS) to explore how such genetic risk manifests in young, high-risk adults. We postulated that BD-PRS would be associated with risk factors for BD. Methods: A final sample of 185 young, high-risk German adults (aged 18-35 years) were grouped into three risk groups and compared to a healthy control group (n = 1,100). The risk groups comprised 117 cases with attention deficit hyperactivity disorder (ADHD), 45 with major depressive disorder (MDD), and 23 help-seeking adults with early recognition symptoms [ER: positive family history for BD, (sub)threshold affective symptomatology and/or mood swings, sleeping disorder]. BD-PRS was computed for each participant. Logistic regression models (controlling for sex, age, and the first five ancestry principal components) were used to assess associations of BD-PRS and the high-risk phenotypes. Results: We observed an association between BD-PRS and combined risk group status (OR = 1.48, p < 0.001), ADHD diagnosis (OR = 1.32, p = 0.009), MDD diagnosis (OR = 1.96, p < 0.001), and ER group status (OR = 1.7, p = 0.025; not significant after correction for multiple testing) compared to healthy controls. Conclusions: In the present study, increased genetic risk for BD was a significant predictor for MDD and ADHD status, but not for ER. These findings support an underlying shared risk for both MDD and BD as well as ADHD and BD. Improving our understanding of the underlying genetic architecture of these phenotypes may aid in early identification and risk stratification.},
  language  = {en}
}
@article{BrevikvanDonkelaarWeberetal.2016,
  author    = {Brevik, Erlend J and van Donkelaar, Marjolein M. J. and Weber, Heike and S{\´a}nchez-Mora, Cristina and Jacob, Christian and Rivero, Olga and Kittel-Schneider, Sarah and Garcia-martinez, Iris and Aebi, Marcel and van Hulzen, Kimm and Cormand, Bru and Ramos-Quiroga, Josep A and Lesch, Klaus-Peter and Reif, Andreas and Ribases, Marta and Franke, Barbara and Posserud, Maj-Britt and Johansson, Stefan and Lundervold, Astri J. and Haavik, Jan and Zayats, Tetyana},
  title     = {Genome-wide analyses of aggressiveness in attention-deficit hyperactivity disorder},
  series = {American Journal of Medical Genetics Part B-Neuropsychiatric Genetics},
  volume    = {171B},
  journal   = {American Journal of Medical Genetics Part B-Neuropsychiatric Genetics},
  number    = {5},
  organization    = {IMAGE Consortium},
  doi       = {10.1002/ajmg.b.32434},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-188116},
  pages     = {733-747},
  year      = {2016},
  abstract  = {Aggressiveness is a behavioral trait that has the potential to be harmful to individuals and society. With an estimated heritability of about 40\%, genetics is important in its development. We performed an exploratory genome-wide association (GWA) analysis of childhood aggressiveness in attention deficit hyperactivity disorder (ADHD) to gain insight into the underlying biological processes associated with this trait. Our primary sample consisted of 1,060 adult ADHD patients (aADHD). To further explore the genetic architecture of childhood aggressiveness, we performed enrichment analyses of suggestive genome-wide associations observed in aADHD among GWA signals of dimensions of oppositionality (defiant/vindictive and irritable dimensions) in childhood ADHD (cADHD). No single polymorphism reached genome-wide significance (P<5.00E-08). The strongest signal in aADHD was observed at rs10826548, within a long noncoding RNA gene (beta = -1.66, standard error (SE) = 0.34, P = 1.07E-06), closely followed by rs35974940 in the neurotrimin gene (beta = 3.23, SE = 0.67, P = 1.26E-06). The top GWA SNPs observed in aADHD showed significant enrichment of signals from both the defiant/vindictive dimension (Fisher's P-value = 2.28E-06) and the irritable dimension in cADHD (Fisher's P-value = 0.0061). In sum, our results identify a number of biologically interesting markers possibly underlying childhood aggressiveness and provide targets for further genetic exploration of aggressiveness across psychiatric disorders.},
  language  = {en}
}
@article{GrimmWeberKittelSchneideretal.2020,
  author    = {Grimm, Oliver and Weber, Heike and Kittel-Schneider, Sarah and Kranz, Thorsten M. and Jacob, Christian P. and Lesch, Klaus-Peter and Reif, Andreas},
  title     = {Impulsivity and Venturesomeness in an Adult ADHD Sample: Relation to Personality, Comorbidity, and Polygenic Risk},
  series = {Frontiers in Psychiatry},
  volume    = {11},
  journal   = {Frontiers in Psychiatry},
  issn      = {1664-0640},
  doi       = {10.3389/fpsyt.2020.557160},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-219751},
  year      = {2020},
  abstract  = {While impulsivity is a basic feature of attention-deficit/hyperactivity disorder (ADHD), no study explored the effect of different components of the Impulsiveness (Imp) and Venturesomeness (Vent) scale (IV7) on psychiatric comorbidities and an ADHD polygenic risk score (PRS). We used the IV7 self-report scale in an adult ADHD sample of 903 patients, 70\% suffering from additional comorbid disorders, and in a subsample of 435 genotyped patients. Venturesomeness, unlike immediate Impulsivity, is not specific to ADHD. We consequently analyzed the influence of Imp and Vent also in the context of a PRS on psychiatric comorbidities of ADHD. Vent shows a distinctly different distribution of comorbidities, e.g., less anxiety and depression. PRS showed no effect on different ADHD comorbidities, but correlated with childhood hyperactivity. In a complementary analysis using principal component analysis with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition ADHD criteria, revised NEO Personality Inventory, Imp, Vent, and PRS, we identified three ADHD subtypes. These are an impulsive-neurotic type, an adventurous-hyperactive type with a stronger genetic component, and an anxious-inattentive type. Our study thus suggests the importance of adventurousness and the differential consideration of impulsivity in ADHD. The genetic risk is distributed differently between these subtypes, which underlines the importance of clinically motivated subtyping. Impulsivity subtyping might give insights into the organization of comorbid disorders in ADHD and different genetic background.},
  language  = {en}
}
@article{PalladinoChiocchettiFranketal.2020,
  author    = {Palladino, Viola Stella and Chiocchetti, Andreas G. and Frank, Lukas and Haslinger, Denise and McNeill, Rhiannon and Radtke, Franziska and Till, Andreas and Haupt, Simone and Br{\"u}stle, Oliver and G{\"u}nther, Katharina and Edenhofer, Frank and Hoffmann, Per and Reif, Andreas and Kittel-Schneider, Sarah},
  title     = {Energy metabolism disturbances in cell models of PARK2 CNV carriers with ADHD},
  series = {Journal of Clinical Medicine},
  volume    = {9},
  journal   = {Journal of Clinical Medicine},
  number    = {12},
  issn      = {2077-0383},
  doi       = {10.3390/jcm9124092},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220074},
  year      = {2020},
  abstract  = {The main goal of the present study was the identification of cellular phenotypes in attention-deficit-/hyperactivity disorder (ADHD) patient-derived cellular models from carriers of rare copy number variants (CNVs) in the PARK2 locus that have been previously associated with ADHD. Human-derived fibroblasts (HDF) were cultured and human-induced pluripotent stem cells (hiPSC) were reprogrammed and differentiated into dopaminergic neuronal cells (mDANs). A series of assays in baseline condition and in different stress paradigms (nutrient deprivation, carbonyl cyanide m-chlorophenyl hydrazine (CCCP)) focusing on mitochondrial function and energy metabolism (ATP production, basal oxygen consumption rates, reactive oxygen species (ROS) abundance) were performed and changes in mitochondrial network morphology evaluated. We found changes in PARK2 CNV deletion and duplication carriers with ADHD in PARK2 gene and protein expression, ATP production and basal oxygen consumption rates compared to healthy and ADHD wildtype control cell lines, partly differing between HDF and mDANs and to some extent enhanced in stress paradigms. The generation of ROS was not influenced by the genotype. Our preliminary work suggests an energy impairment in HDF and mDAN cells of PARK2 CNV deletion and duplication carriers with ADHD. The energy impairment could be associated with the role of PARK2 dysregulation in mitochondrial dynamics.},
  language  = {en}
}