Brain Changes Linked to Worse Cognitive Performance in Professional Fighters

By Will Boggs MD

September 11, 2019

NEW YORK (Reuters Health) - Two structural brain changes on MRI, cavum septum pellucidum (CSP) and cavum vergae (CV), are associated with smaller brain volumes and worse cognitive performance in professional fighters, according to findings from the ongoing Professional Fighters Brain Health Study (PFBHS).

"I hope that physicians who care for patients exposed to repetitive trauma with a 'normal' routine MRI with 'just a CSP or CV' would not summarily dismiss the patient, but consider advanced imaging (volumetric imaging, diffusion tensor imaging (DTI)) and specific neurotrauma clinical follow-up (advanced cognitive and mood testing) for further evaluation," Dr. Jonathan K. Lee of the Cleveland Clinic, in Ohio, told Reuters Health by email.

Repetitive head trauma is associated with various neurodegenerative disorders, but studies of structural brain changes in athletes with a history of repetitive head trauma have yielded inconsistent findings. CSP and CV, for instance, are often described as normal variants in MRI reports.

Dr. Lee and colleagues examined possible associations between CSP and CV, various brain volume measurements, and cognitive and mood outcomes in their study of 476 professional fighters and 63 healthy age-matched controls.

Compared with controls, fighters had 4.64-fold higher odds of CSP and 24.8-fold higher odds of CV, both significant findings. They also had significantly lower volumes in the thalamus and corpus callosum, lower processing speed and lower psychomotor speed.

Fighters with CV had significantly lower mean psychomotor speed and lower mean brain volumes in the supratentorium and other structures, compared with fighters without CV, the researchers report in JAMA Neurology, online September 9.

Longer CSP/CV was also associated with significantly lower processing speed, lower psychomotor speed and lower brain volumes in the supratentorium and other structures.

Among 125 fighters with CSP followed for a median 2.8 years, the length of the CSP/CV increased a mean 1.0 mm, and the maximum transverse width of the CSP increased a mean 0.2 mm, but these changes were not associated with changes in brain volumes or cognitive scores.

In a subanalysis, the presence of CV was not associated with decreased intracranial volumes among active fighters, but the association between increased CSP/CV length and brain volumes and processing and psychomotor speeds persisted.

Among retired fighters, none of the associations between CV, CSP/CV length, and processing and psychomotor speeds were observed.

However, the researchers caution that the subanalysis was underpowered in both groups because of the small number of retired fighters and because the retired fighters differed significantly from the active fighter group in terms of age and fighting exposure.

"In patients exposed to repetitive trauma, physicians and radiologists cannot just dismiss CSP and CV as incidental findings," Dr. Lee said. "More research is warranted, including following this patient cohort long-term, where eventually pathologic correlates for these findings may be more closely examined."


JAMA Neurol 2019.