Olfactory function is reduced in a subset of former elite American football players with traumatic encephalopathy syndrome.

This article investigates whether hyposmia (reduced sense of smell) is present in traumatic encephalopathy syndrome (TES), a clinical disorder associated with chronic traumatic encephalopathy (CTE), in former American football players. Using the Brief Smell Identification Test (B-SIT) and the 2021 National Institute of Neurological Disorders and Stroke (NINDS) consensus diagnostic criteria for TES, the study assessed 179 former professional and college football players alongside 54 asymptomatic, unexposed men. Results showed no overall difference in olfactory function between former players and controls or between players with and without TES; however, those with TES classified as "Possible" or "Probable" CTE had significantly lower B-SIT scores and a higher prevalence of hyposmia compared to those with no TES or "Suggestive" CTE. The findings suggest that hyposmia may serve as a clinical biomarker for more advanced CTE pathology in former football players, though the study lacked autopsy confirmation and acknowledges limitations including the screening nature of the B-SIT and potential selection bias.