Hippocampal Resting-State Functional Connectivity Forecasts Individual Posttraumatic Stress Disorder Symptoms: A...

Area of Science:

• Neuroscience
• Psychiatry
• Radiology

Background:

• Posttraumatic stress disorder (PTSD) is a significant mental health challenge with no reliable predictors for its development after trauma.
• Chronic PTSD is associated with altered resting-state functional connectivity (rsFC) in the hippocampus and its connections to other brain regions.
• Previous research, limited by small sample sizes, suggested hippocampal rsFC acutely after trauma might predict future PTSD severity.

Purpose of the Study:

• To investigate if whole-brain hippocampal rsFC patterns, using a data-driven approach, can predict the development of PTSD symptoms.
• To identify potential early neuroimaging biomarkers for PTSD risk assessment.

Main Methods:

• Ninety-eight adults at risk for PTSD underwent resting-state functional magnetic resonance imaging (rsFC) within one month of traumatic injury.
• Whole-brain rsFC with the hippocampus was analyzed using machine learning (kernel ridge regression) with cross-validation.
• PTSD symptom severity was assessed six months later using the Clinician-Administered PTSD Scale for DSM-5.

Main Results:

• Acute hippocampal rsFC significantly predicted PTSD symptom severity at six months (r=0.30, p=0.006).
• The predictive value of hippocampal rsFC remained significant after controlling for baseline PTSD symptoms and other psychological factors like depression and anxiety.
• The model explained 9% of the variance in PTSD symptom severity (R²=0.09, p=0.025).

Conclusions:

• Functional connectivity of the hippocampus across the brain, measured acutely after trauma, is associated with future PTSD symptom severity.
• Hippocampal rsFC shows promise as an early predictive biomarker for PTSD development.
• This data-driven approach provides a more comprehensive understanding of hippocampal connectivity in predicting PTSD outcomes.