Neuroimaging of Cognitive Dysfunction and Depression in Aging Retired National Football League Players

Abstract

To assess cognitive impairment and depression in aging former professional football (National Football League [NFL]) players and to identify neuroimaging correlates of these dysfunctions. Design:We compared former NFL players with cognitive impairment and depression, cognitively normal retired players who were not depressed, and matched healthy control subjects.Setting: Research center in the North Texas region of the United States.Patients: Cross-sectional sample of former NFL players with and without a history of concussion recruited from the North Texas region and age-, education-, and IQ-matched controls. Thirty-four retired NFL players (mean age, 61.8 years) underwent neurological and neuropsychological assessment. A subset of 26 players also underwent detailed neuroimaging; imaging data in this subset were compared with imaging data acquired in 26 healthy matched controls.Main Outcome Measures: Neuropsychological measures, clinical diagnoses of depression, neuroimaging mea-sures of white matter pathology, and a measure of cerebral blood flow.Results: Of the 34 former NFL players, 20 were cognitively normal. Four were diagnosed as having a fixed cognitive deficit; 8, mild cognitive impairment; 2, dementia; and 8, depression. Of the subgroup in whom neuroimaging data were acquired, cognitively impaired participants showed the greatest deficits on tests of naming, word finding, and visual/verbal episodic memory. We found significant differences in white matter abnormalities in cognitively impaired and depressed retired players compared with their respective controls. Regional blood flow differences in the cognitively impaired group (left temporal pole, inferior parietal lobule, and superior temporal gyrus) corresponded to regions associated with impaired neurocognitive performance (problems with memory, naming, and word finding). Conclusions:Cognitive deficits and depression appear to be more common in aging former NFL players compared with healthy controls. These deficits are correlated with white matter abnormalities and changes in regional cerebral blood flow.

Lifelong behavioral and neuropathological consequences of repetitive mild traumatic brain injury

“…Collectively, with the results of our previously published work,13, 19 spatial learning performance and executive function as measured by escape latency and distance travelled for both s‐mTBI and r‐mTBI groups was poorer than their respective controls, despite the age‐related decrease in performance observed across all groups. These findings are consistent with observations in the human population in which those suffering from repetitive mTBI appear to also have cognitive deficits when compared with healthy controls 28. Although there is no clinical study to support this observation, our data also suggest that the neurobehavior of the singly injured animals was normal for most of their lives, but the last 6 months of their lifespan saw rapidly diminishing cognitive performance.…”

“…Repetitive mTBI is clinically associated with symptoms of irritability, impulsivity, aggression, depression, short‐term memory loss, heightened suicidality, concentration difficulties, and sleep disturbance 6. A recent series of studies have demonstrated that cognitive deficits are more common in former athletes who sustained sport concussions when compared with age‐matched control patients 26, 27, 28, 29, 30. This spectrum of behavioral changes falls in line with our preclinical data implicating the consequences of repetitive mTBI in the development of chronic neurological sequelae.…”

White Matter Changes and Confrontation Naming in Retired Aging National Football League Athletes

“…35 We used the Bayesian information criterion (BIC) to identify the best set of variables, among the previously mentioned assessments, that would best predict FA at the voxel level across the entire white matter skeleton. 34 The residual noise variance was calculated for each variable combination at the voxel level and subjected to the BIC.…”

“…38 This study focuses on only one cognitive domain; however, other tests of cognition were significant as described by Hart and coworkers, 35 and we adjusted our p value to compensate (Bonferonni correction p < 0.02). Age was regressed from the imaging data prior to the execution of Randomise to make the imaging data comparable to the BNT T-scores that were already stratified for age.…”

“…White matter pathway disruption as assessed by FA has been correlated with performance on some neuropsychological tasks, 16,29,30 including naming performance. 31 Professional football players who experienced subconcussive head impacts 32,33 may be susceptible to increased risk for progressive cognitive decline and affective disorders 34,35 with aging. 32,33 A subconcussive impact is defined as any blow to the head that does not result in a concussion.…”