Physical Activity in Community‐Dwelling Older Persons With Mild Traumatic Brain Injury

Abstract

AbstractBackgroundTo examine the association between traumatic brain injury (TBI) and physical activity in older adults.MethodWe conducted a cross‐sectional analysis of 944 older persons (mean age = 85, SD = 7.48 years; 77% female) at their last available physical activity measure from the Rush Memory and Aging Project. Physical activity was measured 24 hours per day for 7‐10 days with wrist‐worn actigraphy (Actical; Philips Respironics, Bend, OR). We analyzed two separate outcomes from actigraphy: total daily activity and intensity of daily activity. To account for positive skewness, we applied a logarithmic transformation. TBI status was assessed by self‐report. We classified the participants as 1) TBI with loss of consciousness (LOC), 2) TBI without LOC, or 3) no TBI exposure (reference group). Multiple linear regression analyses, adjusted for age, education, and sex, were used to examine TBI with LOC and TBI with no LOC as separate predictors in a single model for each actigraphy outcome.ResultA history of TBI was reported in 351 (37%) participants, of whom 89 (9%) had at least one TBI with LOC and 262 (28%) had TBIs that did not result in LOC. Individuals with TBI with LOC had less total daily physical activity, with their total daily physical activity being about 19% (95%CI = 3.4%, 32.5%) lower than the reference group. The intensity of daily physical activity in those with TBI with LOC was 10% (95%CI = 0.7%, 18.2%) lower than the reference group. These associations remained after controlling depression, BMI, vascular risk factors, vascular diseases, and motor ability. Those with TBI without LOC did not differ from the reference group in daily physical activity and intensity of daily physical activity. We analyzed a subset of the 944 consisting of 710 deceased individuals who had undergone pathologic examination from postmortem brain tissue. Even after accounting for brain pathologies of Alzheimer’s disease, Lewy bodies, and cerebral infarcts, TBI with LOC remained associated with daily physical activity (p = 0.002).ConclusionOur result suggests that people with a history TBI with LOC may be associated with lower daily physical activity levels independent of the accumulation of diverse brain pathologies.