Autor:innen:
Katharina Brosch, Marburg (Germany)
Frederike Stein, Marburg (Germany)
Julia-Katharina Pfarr, Marburg (Germany)
Kai Gustav Ringwald, Marburg (Germany)
Susanne Meinert, Münster (Germany)
Lena Waltemate, Münster (Germany)
Udo Dannlowski, Münster (Germany)
Axel Krug, Bonn (Germany)
Igor Nenadic, Marburg (Germany)
Tilo T. J. Kircher, Marburg (Germany)
Background: Previous studies comparing the three major psychiatric disorders major depression (MDD), bipolar disorder (BP), and schizophrenia spectrum disorder (SSD; i.e. schizophrenia and schizoaffective disorder) have highlighted their high genetic, phenotypical, and symptomatic overlap. With regard to brain structural overlaps, there is a lack in the literature that directly compares these groups to healthy controls. Transdiagnostically shared risk and protective factors of common morphometric changes are completely elusive.
Method: In an age and sex-matched, we compared gray matter volume (GMV, 3T magnetic resonance imaging) of healthy controls (n=110), MDD (n=110), BP (n=110), and SSD patients (n=110). We applied a conjunction analysis to identify shared GMV alterations across diagnoses. We further investigated associations of significant shared GMV alteration with psychopathology, neuropsychology, early risk and protective factors, as well as current risk and protective factors.
Results: As a common substrate across all disorders we identified GMV reductions in the left hippocampus (k=316, x/y/z=-30/-33/-10.5), T=4.25, p=.042 FWE cluster level; k=316, p=.01 FWE peak level). This cluster was associated with the neuropsychology factor working memory/executive functioning, and with global assessment of functioning (GAF) across all disorders.
Conclusion: Hippocampal grey matter reduction is a transdiagnostic finding across MDD, BD, and SSD irrespective of their diagnosis. Reduced volume in this area was associated with reduced global functioning, reduced performance in working memory and executive domains of neuropsychology. The finding has important implication for further biological research looking beyond phenomenologically defined diagnoses.
Keywords: transdiagnostic, VBM, MDD, BP, SSD, risk factors