Football Players Health Study Publications

Retrospective evaluations of repeated head injury are needed to better understand associations between head injury exposure and later-life deleterious outcomes. However, there is limited assessment of whether head injury recall assessments produce consistent measures over time, and no assessment of whether the reporting is related to current health status. The concussion signs and symptoms scale (CSS; developed for the Football Players Health Study at Harvard University) was designed to measure cumulative head injury exposure history by asking about the frequency of 10 CSS during active football play.

Results suggest that the CSS scale is stable over time and appears robust against changes in health status. The CSS should be considered for other retrospective studies of brain-injured populations to measure prior cumulative concussion history.

Playing in the NFL has been linked to chronic adverse health outcomes. The extent to which NFL players’ careers impact their spouses’ caregiver burden, depression, and anxiety remains unknown. In addition to conventional family stressors, NFL families may have specific concerns such as chronic traumatic encephalopathy (CTE; a condition that can only be established at autopsy), which may additionally contribute to caregiver burden and mood symptoms.

The study found that participants who reported their own health as poor also reported increased levels of caregiver burden, anxiety, and depression compared to those who rated their own health positively. Notably, participants who reported concerns about chronic traumatic encephalopathy (CTE) reported levels of caregiver burdenon par with that of military families, and higher than family members caring for partners with cancer, dementia, or of advanced age. Participants with a history of numerous relocations also reported increased caregiver burden. Higher ratings of marital satisfaction were linked to reduced caregiver burden, anxiety, and depression.

Please read our results return for more information and action items for NFL families.

Concussions sustained during American-style football (ASF) participation are common. Whether concussions are associated with cardiovascular risk is unknown.

In this paper, researchers sought to determine whether concussions sustained during collegiate ASF participation lead to increases in systolic blood pressure (SBP) and acquired maladaptive cardiovascular phenotypes.

The researchers found that concussions sustained during collegiate ASF participation are independently associated with markers of cardiovascular risk and acquired maladaptive cardiovascular phenotypes. Clinical ASF concussion management strategies inclusive of careful BP surveillance may lead to early identification of hypertension.

Career duration is often used as a proxy metric of neurotrauma exposure in health studies of elite and professional athletes, likely due to ease of recall and verification using public records. However, important considerations related to its use in this setting have not been investigated.

In this study of former professional American-style football (ASF) players, former players with both the shortest and longest careers had comparatively lower risk of adverse health outcomes when compared with players with midrange career lengths. In addition, former professional ASF players with the longest careers reported fewer adverse play-related exposures (eg, concussion history and average number of snaps per game).

Relationships between ASF career duration and subsequent health status may be non-linear. Specifically, attenuation of associations among longer career players could be related to selection effects resulting in reduced susceptibility of longer career players to certain exposures or to career length serving as a poor proxy for true causal factors.

CTE, or chronic traumatic encephalopathy, is a real condition resulting from repetitive head injury that is identified on autopsy. Currently there is no test that can confirm whether a living person has CTE, nevertheless, former NFL players may be concerned that they have CTE. Our objective was to determine how many players shared this concern, and whether they had other conditions that cause cognitive symptoms that might mimic CTE symptoms. Lastly, we studied whether frequent thoughts of self harm or suicide were common in former players who believe they have CTE.

Please read our results return for more information and action items for former players.

Intraarticular knee injuries and subsequent posttraumatic arthritis (PTOA) are common in athletes. Unfortunately, PTOA may significantly affect performance and overall function, but this condition remains difficult to characterize. In this review, we provide an overview of imaging modalities used to evaluate PTOA among athletes and physically active individuals following knee injury, with the goal to discuss the strengths and limitations of their application in this population.

Prior studies examining small samples of symptomatic former professional football players suggest that earlier age of first exposure (AFE) to American football is associated with adverse later life health outcomes. Our study examined a larger, more representative sample of former professional American football players to assess associations between AFE before age 12 and clinical outcomes compared with those who started at age 12 or older.

In a large cohort of former professional (4,198) American-style football players, we found that AFE was not independently associated with adverse later life outcomes. These findings are inconsistent with smaller studies of former professional football players. Studies examining AFE in professional football players may have limited utility and generalizability regarding policy implications for youth sports.

Please read our results return for more information and action items for former players.

Mid-life cardiovascular risk factors are associated with later cognitive decline. Whether repetitive head injury among professional athletes impacts cardiovascular risk is unknown. We investigated associations between concussion burden and post-career hypertension, high cholesterol, and diabetes among former NFL players. We found that prior concussion burden is associated with post-career atherosclerosis cardiovascular risk profiles among former NFL football players.

Please read our results return for more information and action items for former players.

Traumatic brain injury (TBI) is independently associated with hypertension and ischemic stroke. The goal of this study was to determine the interplay between TBI and incident hypertension in the occurrence of post-TBI stroke.

We found that our data offer evidence of an underpinning mechanism linking TBI with ischemic stroke, suggesting potentially overlapping biological mechanisms that may be responsive to pharmacological intervention. These results support the concept that TBI is a complex chronic multi-system disease that increases the risk of ischemic stroke.

Consensus criteria for traumatic encephalopathy syndrome (TES) specify that at least one core clinical feature of cognitive impairment (CI; e.g., difficulties with memory, executive function) or neurobehavioral dysregulation (ND; e.g., explosiveness, rage, and mood lability) be present and not fully accounted for by other health disorders. Associations between self-reported symptoms that mirror the core clinical features of TES—and how they may be related to concomitant medical conditions—remain unclear.

In this large cohort study of 1741 former professional ASF players, several medical conditions and higher concussion exposures were associated with higher odds of reporting clinical TES symptoms. It is important for clinicians to screen for and treat these conditions as appropriate, given that many of these conditions are responsive to treatment. Living with untreated conditions may lead the patient and their healthcare team to misattribute symptoms of a medical condition to TES. Because no validated in vivo criteria exist, it is impossible to determine whether the clinical phenotypes observed are related to (or co-occur with) existing neuropathology.