Mild Cognitive Impairment in Retired Professional Football Players With a History of Mild Traumatic Brain Injury: A Pilot Investigation

Effects of Cumulative Head Impact Exposure in Adolescent Male Contact and Collision Sport Student Athletes

OBJECTIVE

This prospective cohort study aimed to investigate the association between head impact exposure (HIE) and neuropsychological sequelae in high school football and ice hockey players over 1 year.

SETTING

Community sample.

PARTICIPANTS

A cohort of 52 adolescent American football and ice hockey players were enrolled in the study, with a final study sample of 35 included in analyses.

DESIGN

The study followed a prospective cohort design, with participants undergoing neuropsychological screening and accelerometer-based measurement of HIE over 1 season.

MAIN MEASURES

Changes in cognition, emotions, behavior, and reported symptoms were assessed using standardized neuropsychological tests and self-reported questionnaires.

RESULTS

Cumulative HIE was not consistently associated with changes in cognition, emotions, behavior, or reported symptoms. However, it was linked to an isolated measure of processing speed, showing inconsistent results based on the type of HIE. History of previous concussion was associated with worsened verbal memory recognition (ImPACT Verbal Memory) but not on a more robust measure of verbal memory (California Verbal Learning Test [CVLT]). Reported attention-deficit/hyperactivity disorder history predicted improved neurocognitive change scores. No associations were found between reported history of anxiety/depression or headaches/migraines and neuropsychological change scores.

CONCLUSION

Overall, our findings do not support the hypothesis that greater HIE is associated with an increase in neuropsychological sequelae over time in adolescent football and ice hockey players. The results align with the existing literature, indicating that HIE over 1 season of youth sports is not consistently associated with significant neuropsychological changes. However, the study is limited by a small sample size, attrition over time, and the absence of performance validity testing for neurocognitive measures. Future studies with larger and more diverse samples, longer follow-up, and integration of advanced imaging and biomarkers are needed to comprehensively understand the relationship between HIE and neurobehavioral outcomes. Findings can inform guidelines for safe youth participation in contact sports while promoting the associated health and psychosocial benefits.

Soccer's AI transformation: deep learning's analysis of soccer's pandemic research evolution

Introduction

This paper aims to identify and compare changes in trends and research interests in soccer articles from before and during the COVID-19 pandemic.

Methods

We compared research interests and trends in soccer-related journal articles published before COVID-19 (2018-2020) and during the COVID-19 pandemic (2021-2022) using Bidirectional Encoder Representations from Transformers (BERT) topic modeling.

Results

In both periods, we categorized the social sciences into psychology, sociology, business, and technology, with some interdisciplinary research topics identified, and we identified changes during the COVID-19 pandemic period, including a new approach to home advantage. Furthermore, Sports science and sports medicine had a vast array of subject areas and topics, but some similar themes emerged in both periods and found changes before and during COVID-19. These changes can be broadly categorized into (a) Social Sciences and Technology; (b) Performance training approaches; (c) injury part of body. With training topics being more prominent than match performance during the pandemic; and changes within injuries, with the lower limbs becoming more prominent than the head during the pandemic.

Conclusion

Now that the pandemic has ended, soccer environments and routines have returned to pre-pandemic levels, but the environment that have changed during the pandemic provide an opportunity for researchers and practitioners in the field of soccer to detect post-pandemic changes and identify trends and future directions for research.

Longitudinal Outcomes of Cumulative Impact Exposure on Oculomotor Functioning in Professional Motorsport Drivers

Importance

Professional motorsport drivers are regularly exposed to biomechanical forces comparable with those experienced by contact and collision sport athletes, and little is known about the potential short-term and long-term neurologic sequelae.

Objective

To determine whether cumulative impact exposure is associated with oculomotor functioning in motorsport drivers from the INDYCAR professional open-wheel automobile racing series.

Design, Setting, and Participants

This is a longitudinal retrospective cohort study conducted across 3 racing seasons (2017-2019). Statistical analyses were conducted in November 2021. Data were retrieved from a secondary care setting associated with the INDYCAR series. INDYCAR series drivers who participated in 3 professional level racing seasons and were involved in at least 1 contact incident (ie, crash) in 2 of the 3 seasons were included in the study.

Exposure

Cumulative acceleration and deceleration forces and total contact incidents (ie, crashes) measured via accident data recorder third generation chassis and ear accelerometers.

Main Outcomes and Measures

Postseries oculomotor performance, including predictive saccades, vergence smooth pursuit, and optokinetic nystagmus, was measured annually with a head-mounted, clinical eye tracking system (Neurolign Dx 100).

Results

Thirteen drivers (mean [SD] age, 29.36 [7.82] years; all men) sustained median resultant acceleration forces of 38.15 g (observed range, 12.01-93.05 g; 95% CI, 30.62-65.81 g) across 81 crashes. A 2-way multivariate analysis of variance did not reveal a statistically significant association between ear and chassis average resultant g forces, total number of contact incidents, and racing season assessed (F9,12 = 0.955; P = .54; Wilks Λ = 0.44).

Conclusions and Relevance

In this cohort study of professional drivers from the INDYCAR series, there were no statistically significant associations among cumulative impact exposure, racing season assessed, and oculomotor performance. Longitudinal studies across racing seasons using multidimensional examination modalities (eg, neurocognitive testing, advanced imaging, biomarkers, and physical examination) are critical to understand potential neurological and neurobehavioral sequelae and long-term consequences of cumulative impact exposure.

Neurocognitive outcomes of older National Football League retirees

OBJECTIVE

Determine if head-injury exposure relates to later-in-life cognitive decline in older National Football League (NFL) retirees.

METHOD

NFL retirees (aged 50+) with or without cognitive impairment underwent baseline (n = 53) and follow-up (n = 29; 13-59 months later) neuropsychological evaluations. Cognitively normal (CN) retirees (n = 26) were age- and education-matched to healthy controls (n = 26). Cognitively impaired (CI) retirees with mild cognitive impairment or dementia (n = 27) were matched to a clinical sample (CS) by age, sex, education, and diagnosis (n = 83). ANOVAs compared neuropsychological composites at baseline and over time between retirees and their matched groups. Regression models evaluated whether concussions, concussions with loss of consciousness (LOC), or games played predicted neuropsychological functioning.

RESULTS

At baseline, CN retirees had slightly worse memory than controls (M_{CN retirees} = 50.69, SE_{CN retirees} = 1.320; M_{Healthy controls} = 57.08, SE_{Healthy controls} = 1.345; p = 0.005). No other group diferences were observed, and head-injury exposure did not predict neurocognitive performance at baseline or over time.

CONCLUSIONS

Head-injury exposure was not associated with later-in-life cognition, regardless of cognitive diagnosis. Some retirees may exhibit lower memory scores compared to age-matched peers, though this is of unclear clinical significance.

Investigating the relationship between mild traumatic brain injury and Alzheimer's disease and related dementias: a systematic review

The objective of this systematic review is to synthesize the relevant literature published after 2016 to ascertain the current landscape of science that relates mild traumatic brain injury (mTBI) to the onset of Alzheimer's disease and related dementias (ADRD) and identify areas of need for future research. We conducted database searches and retrieved articles that were published after 2016 that utilized cognitive assessments to understand the relationship between mTBI and ADRD. We identified eight relevant articles in the review process, four of which presented a significant relationship between mTBI and disease or cognitive impairment outcomes. The studies included in this systematic review underscore the need for future research investigating a possible causal relationship between mTBI and ADRDs given the high prevalence of mTBI among brain injury patients and the lack of literature specifically addressing this issue. Future research should standardize the definitions of mTBI, AD, and ADRDs to create reliable and reproducible results that more comprehensively capture the nuances of this relationship.