Research Reports - Functional neuroimaging distinguishes posttraumatic stress disorder from traumatic brain injury
PLoS One. 2015 Jul 1;10(7)
Amen DG(1), Raji CA(2), Willeumier K(1), Taylor D(1), Tarzwell R(3), Newberg
A(4), Henderson TA(5)
BACKGROUND: Traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD)
are highly heterogeneous and often present with overlapping symptomology,
providing challenges in reliable classification and treatment. Single photon
emission computed tomography (SPECT) may be advantageous in the diagnostic
separation of these disorders when comorbid or clinically indistinct.
METHODS: Subjects were selected from a multisite database, where rest and on-task
SPECT scans were obtained on a large group of neuropsychiatric patients. Two
groups were analyzed: Group 1 with TBI (n=104), PTSD (n=104) or both (n=73)
closely matched for demographics and comorbidity, compared to each other and
healthy controls (N=116); Group 2 with TBI (n=7,505), PTSD (n=1,077) or both
(n=1,017) compared to n=11,147 without either. ROIs and visual readings (VRs)
were analyzed using a binary logistic regression model with predicted
probabilities inputted into a Receiver Operating Characteristic analysis to
identify sensitivity, specificity, and accuracy. One-way ANOVA identified the
most diagnostically significant regions of increased perfusion in PTSD compared
to TBI. Analysis included a 10-fold cross validation of the protocol in the
larger community sample (Group 2).
RESULTS: For Group 1, baseline and on-task ROIs and VRs showed a high level of
accuracy in differentiating PTSD, TBI and PTSD+TBI conditions. This carefully
matched group separated with 100% sensitivity, specificity and accuracy for the
ROI analysis and at 89% or above for VRs. Group 2 had lower sensitivity,
specificity and accuracy, but still in a clinically relevant range. Compared to
subjects with TBI, PTSD showed increases in the limbic regions, cingulum, basal
ganglia, insula, thalamus, prefrontal cortex and temporal lobes.
CONCLUSIONS: This study demonstrates the ability to separate PTSD and TBI from
healthy controls, from each other, and detect their co-occurrence, even in highly
comorbid samples, using SPECT. This modality may offer a clinical option for
aiding diagnosis and treatment of these conditions.