Self‐Reported Head Trauma Predicts Poor Dual Task Gait in Retired National Football League Players

OBJECTIVE: Symptomatic head trauma associated with American‐style football (ASF) has been linked to brain pathology, along with physical and mental distress in later life. However, the longer‐term effects of such trauma on objective metrics of cognitive–motor function remain poorly understood. We hypothesized that ASF‐related symptomatic head trauma would predict worse gait performance, particularly during dual task conditions (ie, walking while performing an additional cognitive task), in later life. METHODS: Sixty‐six retired professional ASF players aged 29 to 75 years completed a health and wellness questionnaire. They also completed a validated smartphone‐based assessment in their own homes, during which gait was monitored while they walked normally and while they performed a verbalized serial‐subtraction cognitive task. RESULTS: Participants who reported more symptomatic head trauma, defined as the total number of impacts to the head or neck followed by concussion‐related symptoms, exhibited greater dual task cost (ie, percentage increase) to stride time variability (ie, the coefficient of variation of mean stride time). Those who reported ≥1 hit followed by loss of consciousness, compared to those who did not, also exhibited greater dual task costs to this metric. Relationships between reported trauma and dual task costs were independent of age, body mass index, National Football League career duration, and history of musculoskeletal surgery. Symptomatic head trauma was not correlated with average stride times in either walking condition. INTERPRETATION: Remote, smartphone‐based assessments of dual task walking may be utilized to capture meaningful data sensitive to the long‐term impact of symptomatic head trauma in former professional ASF players and other contact sport athletes. ANN NEUROL 2020;87:75–83