Functional Neuroimaging Distinguishes Autistic Spectrum Disorder from Healthy and Comorbid Conditions in Focused and Large Community Datasets

Background: The diagnosis of Autistic Spectrum Disorders (ASD) relies on history and observation, as no reliable biomarkers have been published.  – Here we performed a retrospective data-mining analysis   of 1,000 (give exact #) ASD patients to investigate whether reliable biomarkers exist for distinguishing ASD from healthy controls in adults, as well as between ASD and non-ASD patient cohorts of adults and children. 

Methods: Subjects were obtained from a multisite psychiatric database which included rest and on task SPECT scans -.  Data analysis was performed across eleven cohorts including – healthy adult controls, adult and child patients with ASD, mood disorders, anxiety disorders, attention deficit hyperactivity disorders (ADHD), and non-ASD matched controls.  Scan regions of interests (ROIs) and visual readings were analyzed using a binary logistic regression model with predicted probabilities inputted into a receiver operating characteristic analysis to identify sensitivity, specificity, and accuracy.  Forward stepwise logistic regression was used to identify the most diagnostically significant regions. 

Results: Rest and on task ROIs and visual readings significantly differentiate – ASD adults from healthy controls as well as ASD adults and children from mood disorders, anxiety disorders, ADHD and non-ASD matched controls.  Decreases in blood flow were observed in the cerebellum, cerebellar vermis, amygdala, and hippocampus; while increases were noted in the anterior cingulate, inferior orbital prefrontal cortex and putamen. Conclusions: Using this method, our findings suggest that SPECT is able to reliably distinguish ASD patients from healthy controls in adults and ASD patients from mood disorders, anxiety disorders, ADHD and non-ASD matched controls in children and adults.  These findings may provide useful diagnostic biomarkers to identify ASD from healthy and comorbid psychiatric disorders.