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Repetitive Head Impacts & Dementia Risk


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Each year, millions of Americans are exposed to repetitive head impacts through contact sports like tackle football, soccer, and ice hockey, physical violence, and military service.

Depending on severity, head impacts can have short-term consequences like headaches, nausea, and dizziness. In the long term, however, repeated impacts can increase a person’s risk for Alzheimer’s disease, and other forms of dementia like chronic traumatic encephalopathy (CTE).

During CTE, brain tissue is damaged, and a protein called tau builds up in the brain. People living with CTE can experience memory and thinking problems, confusion, and behavioral issues like depression and aggression.

Furthermore, unlike Alzheimer’s disease, which develops mostly among older adults, CTE has appeared in much younger individuals. A CTE diagnosis can only be confirmed after death, and there is not currently a cure for the condition.


The Head Impact and Trauma Surveillance Study


Over the last few decades, research has linked severe head injuries to heightened dementia risk. However, less is known about the role of head impacts from routine sports plays (for example, tackling in football or heading the ball in soccer) in a person’s memory, thinking, and functioning over time.

Brain Health Registry researchers are currently collaborating with researchers at Boston University on a project called the Head Impact and Trauma Surveillance Study (HITSS). The goal of this project is to advance understanding of long-term brain health risks from repetitive head impacts in soccer and tackle football.

HITSS researchers are exploring several important questions. These include whether starting to play sports in youth versus adulthood increases risk of later life cognitive issues, and whether level of sports play (for example, high school versus professional), or specific position played makes a difference.

If any of your friends or family members have ever played soccer or tackle football, and are currently age 40 or over, they can follow this link to learn more about what HITSS participation involves or go directly to to enroll in the HITSS study. Participants who complete the entire online survey will be entered into a drawing for a chance to win a $500 gift card.

If you have questions about the HITSS study, please do not hesitate to email