Age of First Football Exposure Linked to Later-Life Cognitive Outcomes

New research suggests the age at which individuals first begin playing tackle football may be associated with later-life cognitive and neurobehavioral outcomes, though not with the presence or severity of chronic traumatic encephalopathy (CTE). A study analyzing the brains of deceased former football players revealed a complex relationship between age of first exposure, CTE pathology, and clinical impairments.

Study Details and Findings

Researchers from Boston University Chobanian &amp. Avedisian School of Medicine and Harvard Medical School analyzed data from 677 deceased male former American football players from the Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) Brain Bank. ¹ The study categorized participants based on age at death – under 60 and 60 or older – and examined their age at first exposure to tackle football, CTE pathology, and cognitive function.

69.6% of donors (471 individuals) had CTE. CTE was more prevalent in the older group (78.3%) compared to the younger group (57.0%). ¹ The severity of CTE increased with age (P <.001).

Interestingly, age at first exposure to tackle football did not predict the presence or stage of CTE. However, in the older cohort, a later age at first exposure was associated with better cognitive, neurobehavioral, and neuropsychiatric scores. ¹ Specifically, each year older at first exposure correlated with lower odds of impairment on measures of executive function and behavioral regulation.

Key Differences Between Age Groups

The younger group (those who died before age 60) had a mean age at first exposure of 10.1 years, played football for an average of 11.1 years, and were less likely to have played professionally compared to the older group. ¹ The younger cohort also exhibited lower rates of Alzheimer’s disease and Lewy body disease. ¹

Implications and Future Research

Whereas repetitive head impacts are known to increase the risk of CTE, ² this study highlights the potential importance of age at first exposure in relation to other neurodegenerative outcomes. The researchers emphasize the need for prospective, population-based studies to further investigate the link between younger age at first exposure to tackle football and long-term clinical impairments.

The study authors concluded that more research is needed to fully understand the complex relationship between age of first exposure to tackle football and clinical impairments. ¹

Understanding CTE and Repetitive Head Impacts

Chronic Traumatic Encephalopathy (CTE) is a neurodegenerative disease linked to repetitive brain trauma, often seen in athletes involved in contact sports. ³ For every 2.6 years of playing tackle football, the risk of developing CTE doubles. ³ However, the development of CTE is not the only potential consequence of repetitive head impacts; other neurodegenerative and cerebrovascular pathologies can also result. ²

¹ Age of First Exposure to Tackle Football and Chronic Traumatic Encephalopathy, NCBI

² Youth Exposure to Repetitive Head Impacts From Tackle Football and Long-term Neurologic Outcomes, ScienceDirect

³ CTE Risk Doubles After 3 Years of Playing Football, Boston University