Cerebral Microbleeds and White Matter Hyperintensities are Associated with Cognitive Decline in an Asian Memory Clinic Study.

BACKGROUND: Cerebral Small Vessel Disease (SVD); lacunes, Cerebral Microbleeds (CMBs), and White Matter Hyperintensities (WMH) have a vital role in cognitive impairment and dementia. SVD in lobar location is related to cerebral amyloid angiopathy, whereas SVD in a deep location with hypertensive arteriopathy. It remains unclear how different locations of SVD affect long-term cognitive decline. The present study aimed to analyse the association between different locations and severity of SVD with global and domain-specific cognitive decline over the follow-up interval of 3 years. METHODS: We studied 428 participants who had performed MRI scans at baseline and at least 3 neuropsychological assessments. Locations of lacunes and CMBs were categorized into strictly lobar, strictly deep and mixed-location, WMH volume into anterior and posterior. The National Institute of Neurological Disorders and Stroke-Canadian Stroke Network Harmonization Neuropsychological Battery was used to assess cognitive function. To analyse the association between baseline location and severity of SVD with cognitive decline, linear regression models with generalized estimated equations were constructed to calculate the mean difference, 95% confidence interval and two-way interaction factor between time and SVD. RESULTS: Increased numbers of baseline CMBs were associated with a decline in global cognition as well as a decline in executive function and memory domains. Location-specific analysis showed similar results with strictly lobar CMBs. There was no association with strictly deep and mixed-location CMBs with cognitive decline. Baseline WMH volume was associated with a decline in global cognition, executive function and memory. Similar results were obtained with anterior and posterior WMH volumes. Lacunes and their locations were not associated with cognitive decline. CONCLUSION: Strictly lobar CMBs, as well as WMH volume in anterior and posterior regions, were associated with cognitive decline. Future research focuses are warranted to evaluate interventions that may prevent cognitive decline related to SVD.

Blood-Based Cardiac Biomarkers and the Risk of Cognitive Decline, Cerebrovascular Disease, and Clinical Events.

Background and Purpose: Cardiac biomarkers, NT-proBNP (N-terminal probrain natriuretic peptide), hs-cTnT (high-sensitivity-cardiac troponin T), and GDF-15 (growth differentiation factor-15) have been proposed as important biomarkers of early vascular pathology. However, little is known of the longitudinal associations of these cardiac biomarkers with cerebrovascular disease and clinical events. We examine the association of blood-based cardiac biomarkers (NT-proBNP, hs-cTnT, and GDF-15) with cognitive decline, incident cerebrovascular disease, vascular events, and mortality. Methods: Four hundred thirty-four memory-clinic patients provided blood samples at baseline, underwent 3 annual neuropsychological assessments and brain magnetic resonance imaging scans at baseline and follow-up. NT-proBNP and hs-cTnT concentrations were measured by electrochemiluminescence immunoassay and GDF-15 by quantitative sandwich immunoassay. Baseline and follow-up magnetic resonance imagings were graded for white matter hyperintensities, lacunes, cerebral microbleeds, cortical infarcts, and intracranial stenosis. Data on incident vascular events and mortality were obtained. Results: Patients with higher levels of NT-proBNP, hs-cTnT, and GDF-15 showed greater decline in memory domain. Additionally, hs-cTnT was associated with decline in global cognition, executive function, and visuomotor speed. Higher levels of NT-proBNP were associated with incident cerebral microbleeds and hs-cTnT with incident cortical infarcts. During a mean follow-up of 3 years, 26 (5.9%) patients died and 35 (8.1%) developed vascular events. Patients with higher levels of NTpro-BNP and hs-cTnT were at increased risk of vascular events whereas those with higher levels of NT-proBNP and GDF-15 were at risk of mortality. Conclusions: Higher levels of blood-based cardiac biomarkers were associated with decline in memory and risk of vascular events and mortality. Moreover, NT-proBNP and hs-cTnT were associated with incident cerebral microbleeds and cortical infarcts. Thus, these biomarkers are potentially useful in identifying patients at risk of adverse vascular events and death.