Cardiovascular risk factors indirectly affect acute post-stroke cognition through stroke severity and prior cognitive impairment: a moderated mediation analysis

Abstract

Background: Cognitive impairment is an important consequence of stroke and transient ischaemic attack, but its determinants are not fully understood. Simple univariable or multivariable models have not shown clinical utility for predicting cognitive impairment. Cardiovascular risk factors may influence cognition through multiple, direct, and indirect pathways, including effects on prior cognition and stroke severity. Understanding these complex relationships may help clinical teams plan intervention and follow-up strategies. Methods: We analysed clinical and demographic data from consecutive patients admitted to an acute stroke ward. Cognitive assessment comprised Abbreviated Mental Test and mini-Montreal Cognitive Assessment. We constructed bias-corrected confidence intervals to test indirect effects of cardiovascular risk factors (hypertension, vascular disease, atrial fibrillation, diabetes mellitus, previous stroke) on cognitive function, mediated through stroke severity and history of dementia, and we assessed moderation effects due to comorbidity. Results: From 594 eligible patients, we included 587 in the final analysis (age range 26-100; 45% female). Our model explained R 2 = 62.10% of variance in cognitive test scores. We found evidence for an indirect effect of previous stroke that was associated with increased risk of prevalent dementia and in turn predicted poorer cognitive score (estimate = − 0.39; 95% bias-corrected CI, − 0.75 to − 0.13; p = 0.02). Atrial fibrillation was associated with greater stroke severity and in turn with a poorer cognitive score (estimate = − 0.27; 95% bias-corrected CI, − 0.49 to − 0.05; p = 0.02). Conversely, previous TIA predicted decreased stroke severity and, through that, lesser cognitive impairment (estimate = 0.38; 95% bias-corrected CI, 0.08 to 0.75; p = 0.02). Through an association with reduced stroke severity, vascular disease was associated with lesser cognitive impairment, conditional on presence of hypertension and absence of diabetes mellitus (estimate = 0.36; 95% bias-corrected CI, 0.03 to 0.68; p = 0.02), although the modelled interaction effects did not reach statistical significance.

Associations between cardiovascular risk factors, stroke severity, and post-stroke cognition: a moderated mediation analysis

“…Our findings were partly different from the study of Drozdowska 2020 19 . Drozdowska thought age and atrial fibrillation indirectly correlated with lower cognitive function through stroke severity.…”

“…The inclusion criteria were: (1) Diagnosis of ischemic stroke was confirmed after admission by MRI 22 ; (2) Patients were admitted within seven days of illness. The exclusion criteria were 19,23,24 25 .…”

“…Nowadays, only few studies learned the moderated and mediated effect in the domain of post-stroke cognitive function 12,[18][19][20] . Drozdowska 2020 studied the effects of cardiovascular disease on PSCI, and they found some risk factors were indirectly associated with the cognition after stroke 19 . However, the association hadn't been learned in China.…”

Urinary 8-OxoGsn as a Potential Indicator of Mild Cognitive Impairment in Frail Patients With Cardiovascular Disease

“…Cardiovascular risk factors and diseases are recognized as predictors of age-related cognitive decline and dementia ( Sahathevan et al, 2012 ). MCI is an important under-researched complication of stroke and transient ischemic attack ( Drozdowska et al, 2020 ). However, it is important to note that no clear correlation between cardiovascular risk factors or diseases and MCI was identified in our study.…”

Urinary 8-OxoGsn as A Potential Indicator of Mild Cognitive Impairment in Frail Patients With Cardiovascular Disease

“…Cardiovascular risk factors are recognized as predictors of age-related cognitive decline and dementia [36]. MCI is an important under-researched complication of stroke and transient ischemic attack [37]. However, it is important to note that in frail patients with CVD, no clear correlation between CVD and MCI has been identi ed, including previous stroke history.…”