Over the course of a lifetime, a variable degree of normal physical and cognitive change occurs. As individuals age, many report these changes as health-related issues. Individuals who have sustained a TBI and live to older adult years, or who sustain a TBI during late adulthood, experience unique and often accelerated declines in physical and mental health. The combination of both brain injury and aging can have serious implications for the patient, their family and the community.
Older adults with brain injury have been found to have poorer functional outcomes compared to younger individuals (Born et al., 1985; Kakarieka et al., 1994; Katz & Alexander, 1994; Ritchie et al. 2000). Only 4% of the older adults with an incoming GCS score of less than eight experienced a good outcome (GOS 4-5), while 91% experienced a poor outcome (GOS 1-3) (Kotwica & Jakubowski 1992). Further, only 5-20% experienced a moderate-to-good recovery one year later (Alberico et al. 1987; Dikmen et al. 1995; Brazinova et al., 2010). Kilaru et al. (1996) reported that lower GCS score is a strong independent predictor of poor long-term functional outcomes in older adults. Ultimately, the research literature has shown that older adults have poorer outcomes at all time points, regardless of the severity of injury (Rothweiler et al. 1998; Vollmer et al. 1991; Katz & Alexander 1994; Mosenthal et al. 2002; Susman et al. 2002; Hukkelhoven et al. 2003; Frankel et al. 2006; LeBlanc et al. 2006).
Older adults admitted to acute care with a severe brain injury have a poor prognosis, with few being discharged with a good functional outcome.
Age and Glasgow Coma Scale scores are independent predictors of poor functional outcome, and good recoveries decline sharply with age.
Disability Rating Scale
Three studies measured how disability rating scale scores changed over time in older individuals with an acquired brain injury (Cifu et al. 1996; Livingston et al. 2005; Frankel et al. 2006). All studies compared older adults to younger individuals at admission to and discharge from an inpatient rehabilitation center. Despite that patients had the same injury severity on admission to rehabilitation, the younger group had greater recovery per day, as measured by disability rating scale scores, compared to the older group (Cifu et al. 1996; Frankel et al. 2006). Thus, while recovery in older adults following TBI is apparent, the process is slower. Conversely, Livingston et al. (2005) found that rates of improvement during the first year are similar in both young and old individuals; however, the rates plateaued/declined over time in older adults while they continued to improve for younger individuals.
Older adults who sustain a TBI recover more slowly, as measured by the Disability Rating Scale, than younger individuals.
Functional Independence measure (FIM)
Many studies have been conducted to measure functional changes over time in individuals with TBI. Graham et al. (2010) studied admission and discharge Functional Independence Measure (FIM) scores and found that older women made similar functional gains as men from admission to discharge, even though they were approximately two years older and were twice as likely to be living at home prior to the brain injury. Other studies have found that younger adults with TBI improved at a greater rate per day compared to older adults based on FIM gain from admission to discharge (Frankel et al. 2006). Upon analysis of FIM subscales during acute care, younger and older adults were similar on physical functioning, but the younger group surpassed the older group in terms of behaviour and cognitive function at almost twice the rate (Cifu et al. 1996).
A significant age effect on overall functional outcome has been found; the older a patient was at the time of injury, the poorer the discharge FIM scores were, despite better admission scores than the younger group (Graham et al. 2010). It should be noted, however, that the authors were unsure how clinically meaningful these differences were (Graham et al. 2010). A side-by-side comparison of admission GCS to discharge FIM revealed that despite the same injury severity in both young and old groups, the older patients with a TBI were discharged with a poorer FIM score for each moderate and severe brain injury sustained (LeBlanc et al., 2006). At one year post-discharge, younger adults recovered significantly better than the older group, even after accounting for pre-morbid conditions (Livingston et al. 2005).
Reeder et al. (1996) did not find that age was a significant predictor of functional gain during rehabilitation, even after controlling for injury etiology, injury severity, and demographic information. The authors suggest that with sufficient rehabilitation lengths of stay, pre-injury functional status is possible in older adults. Given that the lengths of stay in rehabilitation units have decreased over time, the amount of time given to recover to pre-morbid status may not be adequate for patients (Canadian Institute for Health Information 2006). In addition to slower recovery in older adults, there is a clear relationship between increased injury severity and decreased overall function over time (Cifu et al. 1996).
Sustaining a TBI in later years can have a significant effect on overall functioning as measured by the Functional Independence Measure.