Functional brain connectivity and cortical thickness in relation to chronic pain in post-911 veterans and service members with mTBI

ABSTRACT

Objectives: Investigate the relation of chronic pain interference to functional connectivity (FC) of brain regions and to cortical thickness in post-911 Veterans and Service Members (SMs) who sustained a mild traumatic brain injury (mTBI).

Methods: This is an observational study with cross-sectional analyses. A sample of 65 enrollees completing initial evaluation at a single site of the Chronic Effects of Neurotrauma Consortium (CENC) reported pain interference ratings on the TBI QOL. Functional connectivity and cortical thickness were measured.

Results: Severity of pain interference was negatively related to FC of the default mode network (DMN), i.e., participants who reported more severe pain interference had less FC between mesial prefrontal cortex and posterior regions of the DMN including posterior cingulate cortex and precuneus. Cortical thickness of specific regions was positively related to severity of pain interference.

Conclusion: The more that pain was perceived to interfere with daily life, the less the FC between regions in a network associated with self-referential thought and mind wandering. Although cortical thickness in specific brain regions was positively related to severity of pain interference, follow-up longitudinal data, control group data, and study of individual differences in this cohort will expand this initial report and replicate these findings.

KEYWORDS:

• Traumatic brain injury
• pain
• imaging
• functional connectivity
• cortical thickness

Acknowledgements

The CENC Observational Study Group members include: Study leadership: William C. Walker MD (CENC Observational Study Chairman), David X. Cifu MD (consortium PI); Site PIs or co-PIs: Heather G. Belanger PhD (Tampa), Randall Scheibel PhD (Houston), Blessen C. Eapen MD (San Antonio), Carlos Jaramillo MD (San Antonio), Ajit Pai MD (Richmond), Melissa Geurra MD (Fort Belvoir), Terri Pogoda PhD (Boston), Scott Sponheim PhD (Minneapolis), and Kathleen Carlson PhD (Portland). We also acknowledge the efforts of the entire CENC Observational Study Leadership Working Group and Core Team members who also include: Justin Alicea, Jessica Berumen, Cody Blankenship, Jennifer Boyce, Linda Brunson, Katrina Burson, William Carne, Julia Christensen, Margaret Clarke, Sureyya Dikmen, Esra Doud, Connie Duncan, Stephanie Edmunds, Robyn Endsley, Elizabeth Fogleman, Cheryl Ford-Smith, Laura M. Franke, George Gitchel, Katelyn Gormley, Brenda Hair, Jim Henry, Sidney R. Hinds (consortium co-PI), Shawn Hirsch, Nancy Hsu, Caitlin Jones, Kimbra Kenney, Sunchai Khemalaap, Valerie Larson, Henry Lew, Tiffany Lewis, Scott McDonald, Tamara McKenzie-Hartman, Frank Mierzwa, Alison Molitor, Joe Montanari, Johnnie Mortenson, Lauren Nagusuki, Tracy Nolen, Nicholas Pastorek, Judy Pulliam, Risa Richardson, Callie Riggs, Rachel Rosenfield, Sara Salkind, Robert Shin, James K. Sickinger, Taylor Swankie, Nancy Temkin, Doug Theriaque, Maya Troyanskaya, Rodney Vanderploeg, Carmen Vasquez, and Rick Williams (consortium Co-PI).

Additionally, we wish to acknowledge additional members of the CENC Neuroimaging Core including: Marlene Diaz, Nick J. Tustison, James R. Stone, Carlo Pierpaoli, Amritha Nayak, Carmen Velez, Gerald E. York, Jennifer Nathan, Rajan Agarwal, Timothy Duncan, Michael Lennon, Aaron M. Betts, Jorge De Villasante, Robert Cadrain, Garrett Black, Naomi J. Goodrich-Hunsaker, Zili D. Chu, and Rhonda O’Donovan.

This material is based upon work supported with resources and the use of facilities at: Hunter Holmes McGuire Veterans Affairs Medical Center (VAMC) in Richmond, VA; James A. Haley Veterans Hospital (VH), Tampa, FL; Audie L. Murphy Memorial VH, San Antonio, TX; and Michael E. DeBakey VA Medical Center, Houston, TX and is based upon work supported in part by the Defense and Veterans Brain Injury Center, US Army Medical Research and Material Command (USAMRMC).

Declaration of interest

This work was supported by grant funding from: Department of Defense, Chronic Effects of Neurotrauma Consortium (CENC) Award W81X WH-13-2-0095 and Department of Veterans Affairs CENC Award I01 CX001135. The authors report no conflicts of interest. The views, opinions and/or findings contained in this article are those of the authors and should not be construed as an official Veterans Affairs or Department of Defense position, policy or decision, unless so designated by other official documentation.