THURSDAY, Aug. 14, 2025 (HealthDay News) -- Athletes experiencing early-life socioeconomic disadvantage may have an increased risk for neurodegeneration from exposure to repetitive head injury (RHI), according to a study published online Aug. 13 in Neurology.Brooke D. Conway Kleven, P.T., Ph.D., from the NLV Sports Innovation Institute/Kirk Kerkorian School of Medicine in Las Vegas, and colleagues conducted a nested case-control study drawn from a longitudinal cohort to examine whether combat athletes with substantial exposure to RHI with a history of socioeconomic disadvantage have greater neurodegeneration than those from affluent neighborhoods. Data were obtained between 2013 and 2024; brain health was evaluated at annual visits among active and retired professional combat athletes. The athletes were categorized into risk groups based on Area Deprivation Index (ADI), indicating low, moderate, and high socioeconomic deprivation.One hundred athletes were included in the study with an average of five years of data; 20 percent developed progressive cognitive impairment. The researchers found that compared with the low ADI level, at the high ADI level, the thalamus and cerebellar cortex showed significantly lower average volumes by −354.14 and −2,477.84 mm3, respectively, while ventricular volumes were significantly larger among the high versus low ADI groups. Compared with the moderate ADI group, the high ADI group had significantly lower volumes in the hippocampus. These findings remained consistent with and without adjustment for glial fibrillary acidic protein, a proxy for generalized neuroinflammation."The findings support a broader understanding of brain health -- one that considers not just training or fight history, but also the social and economic context in which people live," Kleven said in a statement.One author disclosed ties to the boxing industry.Abstract/Full Text.Sign up for our weekly HealthDay newsletter