Subtle long-term cognitive effects of a single mild traumatic brain injury and the impact of a three-month aerobic exercise intervention

BACKGROUND: Although there is a growing body of literature on the impact of multiple concussions on cognitive function with aging, less is known about the long-term impact of sustaining a single mild traumatic brain injury (mTBI). Additionally, very few interventions exist to treat mTBI patients and prevent a possible accelerated cognitive decline. This study aimed to: 1) examine the long-term effects of a single mTBI on cognition in patients aged between 55 and 70 years old; and 2) evaluate the cognitive effects of an aerobic exercise program for these patients. METHODS: Thirty-five participants (average age: 58.89, SD=4.14) were assessed using neuropsychological tests. Among them, 18 hadsustained a mTBI two to seven years earlier. Significant differences in information processing speed, executive function and visual memory were found between controls and mTBI patients. Sixteen of the mTBI patients then engaged in a 12-week physical exercise program. They were divided into equivalent groups: 1) aerobic training (cycle ergometers); or 2) stretching exercises. The participants' cardiopulmonary fitness (VO2max) was evaluated pre- and postintervention and neuropsychological tests were re-administered postintervention. RESULTS: Participants from the aerobic group significantly improved their fitness compared to the stretching group. However, no between-group difference was found on neuropsychological measures postintervention. CONCLUSIONS: In summary, this study shows long-term cognitive effects of mTBI in late adulthood patients. Moreover, the controlled, 12-week aerobic exercise program did not lead to cognitive improvements in our small mTBI sample. I.Actly, future directions in optimizing mTBI intervention are discussed.