Stratification of MDD and GAD patients by resting state brain connectivity predicts cognitive bias

• Published in: NeuroImage clinical 2018-01, Vol.19, p.425-433
• Main Authors: Bijsterbosch, Janine D., Ansari, Tahereh L., Smith, Stephen, Gauld, Oliver, Zika, Ondrej, Boessenkool, Sirius, Browning, Michael, Reinecke, Andrea, Bishop, Sonia J.
• Format: Article
• Language: English
• Subjects: Adult; Amygdala; Anxiety Disorders - pathology; Anxiety Disorders - physiopathology; Attention; Attention - physiology; Bias; Biomarker; Brain - pathology; Brain Mapping - methods; Cognition - physiology; Connectivity; Depressive Disorder, Major - diagnosis; Depressive Disorder, Major - pathology; Depressive Disorder, Major - physiopathology; Female; Generalized anxiety disorder; Humans; Limbic; Magnetic Resonance Imaging - methods; Major depressive disorder; Male; Middle Aged; Nerve Net - physiopathology; Neural Pathways - physiology; Neural Pathways - physiopathology; Regular; Rest - physiology; Resting state; Stratification; Young Adult
• ISSN: 2213-1582; 2213-1582
• DOI: 10.1016/j.nicl.2018.04.033

Patients with Generalized Anxiety Disorder (GAD) and Major Depressive Disorder (MDD) show between-group comorbidity and symptom overlap, and within-group heterogeneity. Resting state functional connectivity might provide an alternate, biologically informed means by which to stratify patients with GAD or MDD. Resting state functional magnetic resonance imaging data were acquired from 23 adults with GAD, 21 adults with MDD, and 27 healthy adult control participants. We investigated whether within- or between-network connectivity indices from five resting state networks predicted scores on continuous measures of depression and anxiety. Successful predictors were used to stratify participants into two new groups. We examined whether this stratification predicted attentional bias towards threat and whether this varied between patients and controls. Depression scores were linked to elevated connectivity within a limbic network including the amygdala, hippocampus, VMPFC and subgenual ACC. Patients with GAD or MDD with high limbic connectivity showed poorer performance on an attention-to-threat task than patients with low limbic connectivity. No parallel effect was observed for control participants, resulting in an interaction of clinical status by resting state group. Our findings provide initial evidence for the external validity of stratification of MDD and GAD patients by functional connectivity markers. This stratification cuts across diagnostic boundaries and might valuably inform future intervention studies. Our findings also highlight that biomarkers of interest can have different cognitive correlates in individuals with versus without clinically significant symptomatology. This might reflect protective influences leading to resilience in some individuals but not others. •Resting state fMRI markers used to re-stratify patients with GAD and MDD.•Elevated limbic connectivity (LC) linked to high levels of depression.•Patients with high LC showed increased attentional bias towards threat.•LC may be a candidate marker for stratifying patients entering treatment trials.