Citation

Alosco ML, Jarnagin J, Tripodis Y, Platt M, Martin B, Chaisson C, Baugh CM, Fritts NG, Cantu RC, Stern RA. J. Neurotrauma 2016; 34(4): 772-780.

Affiliation

Boston University School of Medicine, Neurology, Neurosurgery, and Anatomy & Neurobiology , 72 East Concord Street , B7800 , Boston, Massachusetts, United States , 02118 ; bobstern@bu.edu.

Copyright

(Copyright © 2016, Mary Ann Liebert Publishers)

DOI

10.1089/neu.2016.4536

PMID

27430424

Abstract

Professional American football players incur thousands of repetitive head impacts (RHI) throughout their lifetime. The long-term consequences of RHI are not well-characterized, but may include olfactory dysfunction. RHI has been associated with changes to brain regions involved in olfaction, and olfactory impairment is common following traumatic brain injury. Olfactory dysfunction is a frequent early sequelae of neurodegenerative diseases (e.g., Alzheimer's), and RHI is associated with the neurodegenerative disease, chronic traumatic encephalopathy (CTE). We examined olfaction, and its association with clinical measures, in former National Football League (NFL) players. Ninety-five former NFL players (ages 40-69) and 28 same-age controls completed a neuropsychological, and neuropsychiatric evaluation as part of an NIH-funded study. The Brief Smell Identification Test (B-SIT) assessed olfaction. Principal Component Analysis generated a four factor structure of the clinical measures: behavioral/mood, psychomotor speed/executive function, and verbal and visual memory. Former NFL players had worse B-SIT scores relative to controls, p=0.0096. A B-SIT cutoff of 11 had the greatest accuracy (c-statistic=0.61) and specificity (79%) for discriminating former NFL players from controls. In the former NFL players, lower B-SIT scores correlated with greater behavioral/mood impairment, p=0.0254, and worse psychomotor speed/executive functioning, p=0.0464, after controlling for age and education. Former NFL players exhibited lower olfactory test scores relative to controls, and poorer olfactory test performance was associated with worse neuropsychological and neuropsychiatric functioning. Future work that uses more comprehensive tests of olfaction and structural and functioning neuroimaging may improve understanding on the association between RHI and olfaction.

Language: en