Interaction between cognitive reserve and age moderates effect of lesion load on stroke outcome

Abstract

The concepts of brain reserve and cognitive reserve were recently suggested as valuable predictors of stroke outcome. To test this hypothesis, we used age, years of education and lesion size as clinically feasible coarse proxies of brain reserve, cognitive reserve, and the extent of stroke pathology correspondingly. Linear and logistic regression models were used to predict cognitive outcome (Montreal Cognitive Assessment) and stroke-induced impairment and disability (NIH Stroke Scale; modified Rankin Score) in a sample of 104 chronic stroke patients carefully controlled for potential confounds. Results revealed 46% of explained variance for cognitive outcome (p < 0.001) and yielded a significant three-way interaction: Larger lesions did not lead to cognitive impairment in younger patients with higher education, but did so in younger patients with lower education. Conversely, even small lesions led to poor cognitive outcome in older patients with lower education, but didn’t in older patients with higher education. We observed comparable three-way interactions for clinical scores of stroke-induced impairment and disability both in the acute and chronic stroke phase. In line with the hypothesis, years of education conjointly with age moderated effects of lesion on stroke outcome. This non-additive effect of cognitive reserve suggests its post-stroke protective impact on stroke outcome.

Hyperintense vessels on imaging account for neurological function independent of lesion volume in acute ischemic stroke

“…This was particularly important for the language measures since total FHV scores did not correlate with these outcomes (see Table 3 ). While age and education correlated with only some outcome measures, both variables were also included in each of our models based on the assumption that these demographic variables contribute to the variance in confrontational naming ( Neils et al, 1995 , Zec et al, 2007 , Tsang and Lee, 2003 , Henderson et al, 1998 , Welch et al, 1996 ), content production ( Yorkston and Beukelman, 1980 , Cooper, 1990 , Ardila and Rosselli, 1996 , Pistono et al, 2017 , Mackenzie, 2000 ), and stroke severity—in terms of the effect of premorbid neurological function on stroke outcomes ( Umarova et al, 2021 , Umarova et al, 2019 , Habeck et al, 2017 ). The MLRM for NIHSS is reported in Table 4 (Model B), in Table 5 for picture naming, and in Table 6 for content production on Cookie Theft picture description.…”

Challenges and Opportunities for the Future of Brain-Computer Interface in Neurorehabilitation

“…Elucidating mechanisms of functional improvement from BCI is further complicated by the fact that brain injured patients have widely heterogenous lesions, and lesion size and location do not predict functional outcomes in a straightforward manner (Umarova et al, 2021). Even in patients with similar extents of impairment, lesion location influences performance of BCI decoding of movement intentions (López-Larraz et al, 2017), and the scalp detected signals are qualitatively different when comparing cortical vs subcortical lesions in particular (López-Larraz et al, 2019).…”

The impact of apraxia and neglect on early rehabilitation outcome after stroke

“…The observed negative effect of age on cognitive stroke recovery has repeatedly been mentioned in the literature. Recently, these effects were also observed for acute stroke patients [45]. A positive impact of education on stroke outcome is known and widely discussed as an indicator of "cognitive reserve" [44], a term comprising acquired mental capacities that have a moderating, protective influence in case of brain damage due to a stroke.…”

“…To this end, previous studies intended to identify predictors of stroke outcome. Typical factors related to recovery after stroke are lesion size and location, age, sex, education, and depression [ 3 , 45 ]. Furthermore, the stroke patients’ cognitive status may influence the functional outcome: While some studies found that general cognitive functioning impacted rehabilitation outcomes [ 26 ], others showed that the prevalence and recovery of cognitive deficits after stroke depended on the cognitive domain affected [ 10 ], which include orientation, speech, praxis, attention, visuospatial abilities, processing speed, and executive functions.…”