Age-dependent association of white matter abnormality with cognition after TIA or minor stroke

Giovanna Zamboni,Sara Mazzucco,Ludovica Griffanti,Peter M Rothwell,Sarah T Pendlebury

doi:10.1212/wnl.0000000000007772

Giovanna Zamboni, Sara Mazzucco + Show 3 more

Open Access

https://doi.org/10.1212/wnl.0000000000007772

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Journal: Neurology	Publication Date: Jun 14, 2019
Citations: 28	License type: cc-by

Affiliation: University of Modena and Reggio Emilia

Abstract

ObjectiveTo investigate if the association between MRI-detectable white matter hyperintensity (WMH) and cognitive status reported in previous studies persists at older ages (>80 years), when some white matter abnormality is almost universally reported in clinical practice.MethodsConsecutive eligible patients from a population-based cohort of all TIA/nondisabling stroke (Oxford Vascular Study) underwent multimodal MRI, including fluid-attenuated inversion recovery and diffusion-weighted imaging, allowing automated measurement of WMH volume, mean diffusivity (MD), and fractional anisotropy (FA) in normal-appearing white matter using FSL tools. These measures were related to cognitive status (Montreal Cognitive Assessment) at age ≤80 vs >80 years.ResultsOf 566 patients (mean [range] age 66.7 [20–102] years), 107 were aged >80 years. WMH volumes and MD/FA were strongly associated with cognitive status in patients aged ≤80 years (all p < 0.001 for WMH, MD, and FA) but not in patients aged >80 years (not significant for WMH, MD, and FA), with age interactions for WMH volume (pinteraction = 0.016) and MD (pinteraction = 0.037). Voxel-wise analyses also showed that lower Montreal Cognitive Assessment scores were associated with frontal WMH in patients ≤80 years, but not >80 years.ConclusionMRI markers of white matter damage are strongly related to cognition in patients with TIA/minor stroke at younger ages, but not at age >80 years. Clinicians and patients should not overinterpret the significance of these abnormalities at older ages.

Highlights

Consecutive eligible patients from a population-based cohort of all TIA/nondisabling stroke (Oxford Vascular Study) underwent multimodal MRI, including fluid-attenuated inversion recovery and diffusion-weighted imaging, allowing automated measurement of white matter hyperintensity (WMH) volume, mean diffusivity (MD), and fractional anisotropy (FA) in normal-appearing white matter using FSL tools
MRI markers of white matter damage are strongly related to cognition in patients with TIA/ minor stroke at younger ages, but not at age >80 years
It has been shown that these diffusion tensor imaging (DTI) measures are abnormal in WMH regions, and in the surrounding normal-appearing white matter (NAWM), and that the level of DTI-detected deterioration of NAWM is associated with age and WMH burden in cognitively healthy adults,[12,13] including those older than 90,14 as well as poststroke patients.[15,16]. These findings suggest that DTI modifications precede the occurrence of WMH and better capture the true extent of pathophysiologic changes underlying global white matter.[17,18]

Summary

Methods

Consecutive eligible patients from a population-based cohort of all TIA/nondisabling stroke (Oxford Vascular Study) underwent multimodal MRI, including fluid-attenuated inversion recovery and diffusion-weighted imaging, allowing automated measurement of WMH volume, mean diffusivity (MD), and fractional anisotropy (FA) in normal-appearing white matter using FSL tools. These measures were related to cognitive status (Montreal Cognitive Assessment) at age ≤80 vs >80 years. After a suspected nondisabling cerebrovascular event (NIH Stroke Scale score

Results

Discussion

Conclusion