Age

In the coming decades, demographic changes will result in a significant increase in the proportion of older individuals all over the globe. For example, in Canada it is estimated that seniors will account for 30% of the population by 2068, an increase of 17% from 2018 (Statistics Canada 2019). When considering epidemiological evidence that found the highest rates of SCI-related hospital admission following trauma in Ontario, Canada was for those over 70 years of age, this has significant implications for the delivery of rehabilitation and support services to this group of patients (Pickett et al. 2006). In addition, many centers in various places around the world provide rehabilitation services to individuals with spinal cord damage as the result of a variety of non-traumatic etiologies and often these people are much older than those injured due to trauma (McKinley et al. 2001; McKinley et al. 2002; New 2005; Scivoletto et al. 2003). Given these trends, it is important to understand the effects of age on rehabilitation outcomes. Several studies have investigated age as an interventional trait to identify which individuals may have better rehabilitation outcomes.

Similar approaches involving case control study designs have been employed by various investigators to examine the effect of age on rehabilitation outcomes. However, in the present review, studies employing some form of matching across different age groups were assessed as representing a higher level of evidence (Cifu et al. 1999; DeVivo et al. 1990; Scivoletto et al. 2003; Seel et al. 2001; Yarkony et al. 1988) as compared to those deemed as having an inadequate method of controlling for potential confounds (Cifu et al. 1999; Kennedy et al. 2003). Several of these studies have demonstrated differences between age groups for a variety of rehabilitation outcomes although there were also some contradictory findings within these studies, albeit some of this may have been due to variation between the sampling frames and methods employed in each study.

For example, Seel et al. (2001) and Cifu et al. (1999) reported reduced rehabilitation LOS for those with paraplegia due to trauma or mixed etiology Osterthun et al. (2009) whereas no differences were seen in investigations of those with tetraplegia due to trauma (Cifu et al. 1999) and also with the mixed sample of people with both traumatic and non-traumatic SCI (Ronen et al. 2004; Scivoletto et al. 2003).

Yarkony et al. (1988) were the first to look at the independent effect of age on rehabilitation outcomes in SCI. This study found that functional outcome was only related to age in patients with complete paraplegia. Among these individuals, Yarkony et al. (1988) demonstrated a trend between the increase in age and increased dependence on seven functional skills including bathing, upper and lower body dressing, stair climbing, and transfers to a chair, toilet, and bath. Yarkony attributed this trend to the fact that there is a “greater residual muscle function” in these individuals. Devivo et al. (1990) later supported this trend by demonstrating an inverse relationship between patients’ age and their level of independence in self-care activities. Anzai et al. (2006) and Eastwood et al. (1999) reported that older individuals were at increased risk of being discharged to an extended care facility due to pre-existing co-morbidities and lack of social and financial support. Similarly, New et al. (2005) reported that younger individuals were more likely to be discharged home.

Conversely, all studies examining functional change showed that younger individuals demonstrated greater functional improvements as indicated by increases in the FIM (i.e., motor FIM scores, change scores, efficiencies) (Cifu et al. 1999; Cifu et al. 1999; Furlan & Fehlings 2009; Pollard & Apple 2003; Seel et al. 2001; van der Putten et al. 2001), BI (Scivoletto et al. 2003) or SCIM (Franceschini et al. 2020). These similar results were obtained from studies involving those with paraplegia (Cifu et al.  1999; Seel et al. 2001), tetraplegia (Cifu et al. 1999), and a mixed sample comprised of those with both traumatic and non-traumatic SCI (Scivoletto et al. 2003). On the other hand, Kennedy et al. (2003) employed the Needs Assessment Checklist developed internally at Stoke-Mandeville, United Kingdom, and demonstrated that there were few systematic age-related differences associated with goal attainment in a mixed traumatic, non-traumatic sample. The Needs Assessment Checklist is a client-focused outcome measure that assesses the degree to which specific behavioural outcomes particularly relevant to the client are achieved. Tchvaloon et al. (2008) (N=143) also reported no significant effect on recovery due to age at injury in an Israeli population of people with traumatic SCI.

In addition to functional outcomes, effective rehabilitation has also been associated with increases in neurological status as indicated by AIS or ASIA motor scores. Of the studies reviewed and utilizing measures of neurological status, both studies limited to those with paraplegia showed no age effects (Cifu et al. 1999; Seel et al. 2001). Conversely, similar studies of those with tetraplegia or a mixed traumatic and non-traumatic SCI sample demonstrated that younger individuals were more likely to make significant neurological gains during inpatient rehabilitation (Cifu et al. 1999; Scivoletto et al. 2003). Additionally, conflicting findings exist in relation to the mechanism of injury with Gupta and colleagues (2008) reporting that traumatic versus non-traumatic injuries are not associated with age. Conversely, McKinley et al. (2008; 1999; 2002) found that non-traumatic injuries are significantly associated with older age.

Despite mixed research regarding the impact of age on SCI rehabilitation, it is reasonable to assume that older individuals require individualized care. In light of this, guidelines established by Rapidi and colleagues (2018) suggest that therapeutic exercise programs in SCI should be prescribed and adapted to each individual’s needs, according to the neurological level of injury, age, and comorbidities.

Conclusions

There is level 3 evidence (from four case control studies: Cifu et al. 1999; Cifu et al. 1999; Osterthun et al. 2009; Seel et al. 2001) that shorter rehabilitation LOS is associated with younger versus older individuals with paraplegia. The same may not be true for those with tetraplegia or for mixed cohorts involving traumatic and non-traumatic SCI.

There is level 3 evidence (from four case control studies: DeVivo et al. 1990; Kennedy et al. 2003; Scivoletto et al. 2003; Yarkony et al. 1988; and one observational study: Franceschini et al. 2020) that age is inversely related to patient’s independence level.

There is level 3 evidence (from five case control studies: Cifu et al. 1999; Cifu et al. 1999; Kennedy et al. 2003; Scivoletto et al. 2003; Seel et al. 2001) that younger as compared to older individuals are more likely to obtain greater functional benefits during rehabilitation.

There is level 3 evidence (from two case control studies: Kennedy et al. 2003; Scivoletto et al. 2003) that significant increases in neurological status during rehabilitation are more likely with younger than older individuals with tetraplegia or for mixed cohorts involving traumatic and non-traumatic SCI. The same may not be true for those with paraplegia.

There is conflicting level 3 evidence (from three case control studies: Gupta et al. 2008; McKinley et al. 1999; McKinley et al. 2002) that older individuals are more likely to experience a non-traumatic than traumatic SCI.

There is level 4 evidence (from one case series: Tchvaloon et al. 2008) that older individuals are more at risk of developing pressure sores.

There is level 4 evidence (from two case series: Anzai et al. 2006; New 2005) that older individuals are more likely to be discharged to an extended care unit.

There is level 4 evidence (from one case series: Eastwood et al. 1999) that age may be associated with a longer length of rehabilitation stay.

There is level 4 and 5 evidence (from two case series and one observational study: Furlan & Fehlings 2009; Pollard & Apple 2003; van der Putten et al. 2001) that younger patients are more likely to experience improved motor outcomes when compared to older individuals. However, both groups experience similar sensory deficits.

There is level 5 evidence (from one observational study: Ronen et al. 2004) that age has no effect on the length of acute hospital stay.