Cognitive characteristics of older adults with history of concussion

Abstract

AbstractBackgroundConcussion is a common injury, and among older adults often results from falls (Thompson, McCormick, & Kagan, 2006). There is some evidence to suggest that older adults with a history of concussion show higher mortality rates than their younger counterparts, as well as increased risk for developing neurodegenerative diseases (such as Alzheimer’s Disease [AD]; Becker, Kapogiannis, & Greig, 2018; Thompson et al., 2006). However, the literature on risk for neurocognitive decline in those with concussion history is limited, and the available evidence is conflicting (Abner et al., 2014). The current study aims to add to the literature regarding the cognitive differences between older adults with and without concussion in a well‐characterized cohort of patients with AD.MethodThis retrospective study investigated cognitive differences in individuals with and without self‐reported concussion history [CH] taking into account age and education level. Participants were enrolled in the Center for Neurodegeneration and Translational Neuroscience and included 52 cognitively normal controls (13 with CH), 68 mild cognitive impairment [MCI] (24 with CH), and 24 mild AD (8 with CH). Cognitive domains assessed included: Global cognitive (MoCA); verbal memory (WMS‐IV Logical Memory; RAVLT); non‐verbal memory (BVMT‐R); attention/working memory (WAIS‐IV Digit Span); verbal set‐shifting (DKEFS Verbal Fluency); and processing speed (SDMT).ResultOmnibus tests did not reveal a significant difference between those with and without CH in the CN, MCI, or AD, groups after taking into account age at time of evaluation and education [CN – F(14,35)=1.20, p>.05; MCI – F(14,46)=0.50, p>.05; AD – F(9,1)=0.66, p>.05, respectively]. Effect sizes (Cohen’s d) for the CN group ranged from small to medium (min=0.1, max=0.7). For MCI, effect sizes were small (min=0.0, max=0.3). For AD, effect sizes ranged from small to medium (min=0.0, max= ‐0.7).ConclusionResults suggest that there are no meaningful differences in cognitive test scores between individuals with and without history of self‐reported concussion after accounting for influences of age and education. Effect sizes were medium despite non‐significant ANCOVAs, suggesting that these results are under‐powered and that future research would find significant results with larger samples. Small sample size and uncertainties regarding self‐report of concussion are limitations of this study.