Neurodegeneration and Vascular Burden on Cognition After Midlife: A Plasma and Neuroimaging Biomarker Study

Background and Objectives: Neurodegeneration and vascular burden are the two most common causes of post-stroke cognitive impairment. However, the interrelationship between the plasma beta-amyloid (A beta) and tau protein, cortical atrophy and brain amyloid accumulation on PET imaging in stroke patients is undetermined. We aimed to explore: (1) the relationships of cortical thickness and amyloid burden on PET with plasma A beta 40, A beta 42, tau protein and their composite scores in stroke patients; and (2) the associations of post-stroke cognitive presentations with these plasma and neuroimaging biomarkers.Methods: The prospective project recruited first-ever ischemic stroke patients around 3 months after stroke onset. The plasma A beta 40, A beta 42, and total tau protein were measured with the immunomagnetic reduction method. Cortical thickness was evaluated on MRI, and cortical amyloid plaque deposition was evaluated by F-18-florbetapir PET. Cognition was evaluated with Mini-Mental State Examination (MMSE), Geriatric Depression Scale (GDS), Dementia Rating Scale-2 (DRS-2).Results: The study recruited 24 stroke patients and 13 normal controls. The plasma tau and tau*A beta 42 levels were correlated with mean cortical thickness after age adjustment. The A beta 42/A beta 40 ratio was correlated with global cortical F-18-florbetapir uptake value. The DRS-2 and GDS scores were associated with mean cortical thickness and plasma biomarkers, including A beta 42/A beta 40, tau, tau*A beta 42, tau/A beta 42, and tau/A beta 40 levels, in stroke patients.Conclusion: Plasma A beta, tau, and their composite scores were associated with cognitive performance 3 months after stroke, and these plasma biomarkers were correlated with corresponding imaging biomarkers of neurodegeneration. Further longitudinal studies with a larger sample size are warranted to replicate the study results.

Automated summary

The study aimed to investigate the relationship between neuroimaging and plasma biomarkers with cognitive performance in stroke patients. The results showed that plasma tau protein and Aβ42 levels were correlated with mean cortical thickness, while the Aβ42/Aβ40 ratio was associated with global cortical amyloid plaque deposition on PET imaging. Overall, plasma Aβ and tau biomarkers were found to be related to cognitive performance in stroke patients.