Associations Between Traumatic Brain Injury Characteristics and Memory Outcomes: Insights from the Health and Retirement Study

Abstract

Traumatic brain injury (TBI) is an established risk factor for accelerated cognitive decline and increased dementia risk. The specific characteristics of TBI (e.g., type of head trauma, presence of a gap in memory, age of onset) that confer the greatest risk to cognitive health remain comparatively less clear. Using data from the 2014 Health and Retirement Study (HRS) experimental module, we examined associations between TBI characteristics and memory outcomes in a national adult lifespan sample. We tested whether the age of onset and presence of a memory gap in TBI resulting from a vehicle accident, from a fall or being hit, or from playing sports or playing on a playground were associated with self-rated memory and recall memory performance in a subsample of HRS respondents across the adult lifespan (N = 414, mean age = 66.28, SD = 9.70, 52% female). In cases where participants reported TBI from three different types of injury (vehicle accident, fall, and playing sports or playing on a playground), they shared whether they experienced a gap in their memory and their age when the head trauma occurred. Participants also reported on self-rated memory and performed a recall memory task. Hierarchical linear regression models were adjusted for age, sex, race, ethnicity, education, and self-rated health. Older age of onset for TBI from a fall was associated with worse self-rated memory (Est. = -0.11, SE = 0.04, p = 0.01) and recall performance (Est. = -0.33, SE = 0.15, p = 0.03). Encountering a memory gap from the TBI that resulted from a vehicle accident (Est. = -0.22, SE = 0.10, p = 0.03), a fall (Est. = -0.23, SE = 0.09, p = 0.01), and from playing sports or playing on a playground (Est. = -0.40, SE = -0.13, p < 0.01) were all significantly associated with worse self-rated memory. Links between encountering a memory gap and recall performance were comparatively scant. Results indicate the impact of TBI on memory varies as a function of type of trauma, age of onset, and presence of memory gap from the head trauma. Our study takes a preclinical, preventative approach to inform public health efforts that target the mitigation of specific types of head trauma at different developmental phases of the lifespan.

Keywords: cognitive health; memory; preclinical dementia risk factors; preventative health; traumatic brain injury.

Figure 1

Sampling of respondents with data from the TBI experimental module from the 2014 core sample of the HRS. Respondents could have reported multiple TBI sources (i.e., Ns of 332, 417, and 178 are non-exclusive sums for respondents with TBI from a vehicle accident, fall, and sport, respectively). Specifically, 52 participants reported TBI from all three sources, 102 participants reported TBI from both a vehicle accident and fall, 10 participants reported TBI from both a vehicle accident and sports-related event, and 65 participants reported TBI from both a fall and sports-related event).

Figure 2

Associations between TBI characteristics and self-rated memory, including effect size estimates for differences. * p < 0.05, ** p < 0.01.

Figure 3

Associations between TBI characteristics and recall memory performance, including effect size estimates for differences. * p < 0.05.