Traumatic brain injury is one of several recognized risk factors for cognitive decline and neurodegenerative disease. Currently, risk scores involving modifiable risk/protective factors for dementia have not incorporated head injury history as part of their overall weighted risk calculation. We investigated the association between the LIfestyle for BRAin Health (LIBRA) risk score with odds of mild cognitive impairment (MCI) diagnosis and cognitive function in older former National Football League (NFL) players, both with and without the influence of concussion history.

Former NFL players, ages ≥ 50 (N=1050; mean age=61.1±5.4-years), completed a general health survey including self-reported medical history and ratings of function across several domains. LIBRA factors (weighted value) included cardiovascular disease (+1.0), hypertension (+1.6), hyperlipidemia (+1.4), diabetes (+1.3), kidney disease (+1.1), cigarette use history (+1.5), obesity (+1.6), depression (+2.1), social/cognitive activity (-3.2), physical inactivity (+1.1), low/moderate alcohol use (-1.0), healthy diet (-1.7). Within Group 1 (n=761), logistic regression models assessed the association of LIBRA scores and independent contribution of concussion history with the odds of MCI diagnosis. A modified-LIBRA score incorporated concussion history at the level planned contrasts showed significant associations across concussion history groups (0, 1-2, 3-5, 6-9, 10+). The weighted value for concussion history (+1.9) within the modified-LIBRA score was based on its proportional contribution to dementia relative to other LIBRA risk factors, as proposed by the 2020 Lancet Commission Report on Dementia Prevention. Associations of the modified-LIBRA score with odds of MCI and cognitive function were assessed via logistic and linear regression, respectively, in a subset of the sample (Group 2; n=289) who also completed the Brief Test of Adult Cognition by Telephone (BTACT). Race was included as a covariate in all models.

The median LIBRA score in the Group 1 was 1.6(IQR= -1, 3.6). Standard and modified-LIBRA median scores were 1.1(IQR= -1.3, 3.3) and 2(IQR= -0.4, 4.6), respectively, within Group 2. In Group 1, LIBRA score was significantly associated with odds of MCI diagnosis (odds ratio[95% confidence interval]=1.27[1.19, 1.28], p <.001). Concussion history provided additional information beyond LIBRA scores and was independently associated with odds of MCI; specifically, odds of MCI were higher among those with 6-9 (Odds Ratio[95% confidence interval]; OR=2.54[1.21, 5.32], p<.001), and 10+ (OR=4.55;[2.21, 9.36], p<.001) concussions, compared with those with no prior concussions. Within Group 2, the modified-LIBRA score was associated with higher odds of MCI (OR=1.61[1.15, 2.25]), and incrementally improved model information (0.04 increase in Nagelkerke R2) above standard LIBRA scores in the same model. Modified-LIBRA scores were inversely associated with BTACT Executive Function (B=-0.53[0.08], p=.002) and Episodic Memory scores (B=-0.53[0.08], p=.002).

Numerous modifiable risk/protective factors for dementia are reported in former professional football players, but incorporating concussion history may aid the multifactorial appraisal of cognitive decline risk and identification of areas for prevention and intervention. Integration of multi-modal biomarkers will advance this person-centered, holistic approach toward dementia reduction, detection, and intervention.