Sex differences in cortical thickness and diffusion properties in patients with traumatic brain injury: a pilot study

ABSTRACT

Objective

Cortical thickness and diffusion properties are important measures of gray and white matter integrity in those with traumatic brain injury (TBI). Many studies show that healthy adult females have greater cortical thickness than males across numerous brain sites. In this study, we explored this sex difference in patients with TBI.

Method

Participants consisted of 32 patients with TBI and 21 neurologically healthy controls. All were scanned by magnetic resonance imaging (MRI). Differences in cortical thickness and diffusion properties were examined between groups (i.e., TBI/control, male/female).

Results

Patients with TBI had more cortical thinning (both hemispheres) compared to controls. They also showed decreased fractional anisotropy (FA) for several major white matter tracts. Healthy females had significantly greater cortical thickness compared to healthy males. However, this difference was smaller among the patients with TBI. We found no sex differences in diffusion properties. There were moderate correlations between cortical thickness, diffusion properties, and cognitive performance, as measured by the Trail Making Test B.

Conclusion

These findings contribute to a growing discussion on sex differences in cortical thickness and diffusion properties. Sexual dimorphism could necessitate different clinical profiles, targets, and rehabilitation strategies in patients with TBI.

KEYWORDS:

• Traumatic brain injury
• sex differences
• cortical thickness
• diffusion properties

Acknowledgments

We would like to thank our veterans at VA Palo Alto Health Care System who took part in this research. We would also like to thank Santa Clara Brain Injury Center for helping us with recruitment. We would like to thank Stacy Moeder, Director of Operations, WRIISC located at VA Palo Alto for her guidance in all hospital-related administrative issues. Funding was provided by the War Related Illness and Injury Study Center, VA Palo Alto Health Care System.

Disclosure statement

The authors declare this research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Additional information

Funding

This work was supported by the War Related Illness and Injury Study Center, VA Palo Alto Health Care System. [ADA0002].