-
Cells Aug 2023Sport concussion affects millions of athletes each year at all levels of sport. Increasing evidence demonstrates clinical and physiological recovery are becoming more... (Review)
Review
Sport concussion affects millions of athletes each year at all levels of sport. Increasing evidence demonstrates clinical and physiological recovery are becoming more divergent definitions, as evidenced by several studies examining blood-based biomarkers of inflammation and imaging studies of the central nervous system (CNS). Recent studies have shown elevated microglial activation in the CNS in active and retired American football players, as well as in active collegiate athletes who were diagnosed with a concussion and returned to sport. These data are supportive of discordance in clinical symptomology and the inflammatory response in the CNS upon symptom resolution. In this review, we will summarize recent advances in the understanding of the inflammatory response associated with sport concussion and broader mild traumatic brain injury, as well as provide an outlook for important research questions to better align clinical and physiological recovery.
Topics: Humans; Brain Concussion; Athletes; Central Nervous System; Inflammation; Macrophage Activation
PubMed: 37681861
DOI: 10.3390/cells12172128 -
JAMA Neurology Oct 2023Young contact sport athletes may be at risk for long-term neuropathologic disorders, including chronic traumatic encephalopathy (CTE).
IMPORTANCE
Young contact sport athletes may be at risk for long-term neuropathologic disorders, including chronic traumatic encephalopathy (CTE).
OBJECTIVE
To characterize the neuropathologic and clinical symptoms of young brain donors who were contact sport athletes.
DESIGN, SETTING, AND PARTICIPANTS
This case series analyzes findings from 152 of 156 brain donors younger than 30 years identified through the Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) Brain Bank who donated their brains from February 1, 2008, to September 31, 2022. Neuropathologic evaluations, retrospective telephone clinical assessments, and online questionnaires with informants were performed blinded. Data analysis was conducted between August 2021 and June 2023.
EXPOSURES
Repetitive head impacts from contact sports.
MAIN OUTCOMES AND MEASURES
Gross and microscopic neuropathologic assessment, including diagnosis of CTE, based on defined diagnostic criteria; and informant-reported athletic history and informant-completed scales that assess cognitive symptoms, mood disturbances, and neurobehavioral dysregulation.
RESULTS
Among the 152 deceased contact sports participants (mean [SD] age, 22.97 [4.31] years; 141 [92.8%] male) included in the study, CTE was diagnosed in 63 (41.4%; median [IQR] age, 26 [24-27] years). Of the 63 brain donors diagnosed with CTE, 60 (95.2%) were diagnosed with mild CTE (stages I or II). Brain donors who had CTE were more likely to be older (mean difference, 3.92 years; 95% CI, 2.74-5.10 years) Of the 63 athletes with CTE, 45 (71.4%) were men who played amateur sports, including American football, ice hockey, soccer, rugby, and wrestling; 1 woman with CTE played collegiate soccer. For those who played football, duration of playing career was significantly longer in those with vs without CTE (mean difference, 2.81 years; 95% CI, 1.15-4.48 years). Athletes with CTE had more ventricular dilatation, cavum septum pellucidum, thalamic notching, and perivascular pigment-laden macrophages in the frontal white matter than those without CTE. Cognitive and neurobehavioral symptoms were frequent among all brain donors. Suicide was the most common cause of death, followed by unintentional overdose; there were no differences in cause of death or clinical symptoms based on CTE status.
CONCLUSIONS AND RELEVANCE
This case series found that young brain donors exposed to repetitive head impacts were highly symptomatic regardless of CTE status, and the causes of symptoms in this sample are likely multifactorial. Future studies that include young brain donors unexposed to repetitive head impacts are needed to clarify the association among exposure, white matter and microvascular pathologic findings, CTE, and clinical symptoms.
Topics: Female; Humans; Male; Young Adult; Adult; Retrospective Studies; Chronic Traumatic Encephalopathy; Brain; Athletes; Athletic Injuries; Soccer
PubMed: 37639244
DOI: 10.1001/jamaneurol.2023.2907 -
Free Neuropathology Jan 20232022 was a productive year for research in traumatic brain injury (TBI) and resultant neuropathology. After an extensive review, we present related studies and...
2022 was a productive year for research in traumatic brain injury (TBI) and resultant neuropathology. After an extensive review, we present related studies and publications which we felt were of particular importance to the neuropathology community. First, 2022 was highlighted by important advancements in the diagnosis and, moreover, our understanding of chronic traumatic encephalopathy (CTE). Important publications include a pair concluding that CTE primarily concerns neuronal accumulation of phosphorylated tau (), but that glial accumulation often helps to facilitate diagnosis. In addition, a new large community study from Australia continues the indication that CTE is relatively uncommon in the community, and the first large-cohort study on brains of military personnel similarly demonstrates that CTE appears to be uncommon among service members and does not appear to explain high rates of neuropsychiatric sequelae suffered by the warfighter. The causation of CTE by impact-type TBI was supported by the application of the Bradford Hill criteria, within the brains of headbutting bovids, and interestingly within an artificial head model exposed to linear impact. Finally, a large-scale analysis of genotypes contends that gene status may influence CTE pathology and outcomes. In experimental animal work, a study using mouse models provided important evidence that TDP-43 facilitates neurodegenerative pathology and is implicated in cognitive dysfunction following TBI, and another study using a swine model for concussion demonstrated that evidence that axonal sodium channel disruption may be a driver of neurologic dysfunction after concussion. Finally, we end with memoriam to Dr. John Q. Trojanowski, a giant of neurodegenerative research and an important contributor to the neurotrauma literature, who we lost in 2022.
PubMed: 37736080
DOI: 10.17879/freeneuropathology-2023-5076 -
Ugeskrift For Laeger Apr 2024Mild traumatic brain injury, such as concussion, was once considered self-resolving. However, over the past decade, increased understanding of the short- and long-term... (Review)
Review
Mild traumatic brain injury, such as concussion, was once considered self-resolving. However, over the past decade, increased understanding of the short- and long-term impact has led to new guidelines for active management. In this review, we summarise recent findings, covering diagnostic criteria, and management for early and persistent symptoms. Many of the postconcussive symptoms can be treated and an individualised approach from a biopsychosocial perspective is recommended. Overall, the new knowledge will significantly impact patient care and future research.
Topics: Humans; Brain Concussion; Post-Concussion Syndrome; Athletic Injuries
PubMed: 38704707
DOI: 10.61409/V10230645