Normal-Appearing White Matter Deteriorates over the Year After an Ischemic Stroke and Is Associated with Global Cognition

Sharmila Sagnier (1, 2) , Gwenaëlle Catheline (1) , Bixente Dilharreguy (1) , Pierre-Antoine Linck (2) , Pierrick Coupé (3, 4) , Fanny Munsch (5) , Antoine Bigourdan (2) , Mathilde Poli (2) , Sabrina Debruxelles (2) , Pauline Renou (2) , Stéphane Olindo (2) , François Rouanet (2) , Vincent Dousset (6, 1) , Thomas Tourdias (6, 1) , Igor Sibon (1, 2)

1 INCIA - Institut de Neurosciences cognitives et intégratives d'Aquitaine
2 CHU Bordeaux
3 LaBRI - Laboratoire Bordelais de Recherche en Informatique
4 PICTURA - Patch-based processing for medical and natural images
5 BIDMC - Beth Israel Deaconess Medical Center [Boston]
6 U1215 Inserm - UB - Neurocentre Magendie : Physiopathologie de la Plasticité Neuronale

Normal-appearing white matter (NAWM) is a hub of plasticity, but data relating to its influence on post-ischemic stroke (IS) outcome remain scarce. The aim of this study was to evaluate the relationship between NAWM integrity and cognitive outcome after an IS. A longitudinal study was conducted including supra-tentorial IS patients. A 3-Tesla brain MRI was performed at baseline and 1 year, allowing the analyses of mean fractional anisotropy (FA) and mean diffusivity (MD) in NAWM masks, along with the volume of white matter hyperintensities (WMH) and IS. A Montreal Cognitive Assessment (MoCA), an Isaacs set test, and a Zazzo's cancellation task were performed at baseline, 3 months and 1 year. Mixed models were built, followed by Tract-based Spatial Statistics (TBSS) analyses. Ninety-five patients were included in the analyses (38% women, median age 69 ± 20). FA significantly decreased, and MD significantly increased between baseline and 1 year, while cognitive scores improved. Patients who decreased their NAWM FA more over the year had a slower cognitive improvement on MoCA (β = - 0.11, p = 0.05). The TBSS analyses showed that patients who presented the highest decrease of FA in various tracts of white matter less improved their MoCA performances, regardless of WMH and IS volumes, demographic confounders, and clinical severity. NAWM integrity deteriorates over the year after an IS, and is associated with a cognitive recovery slowdown. The diffusion changes recorded here in patients starting with an early preserved white matter structure could have long term impact on cognition.

Mots clés: Diffusion tensor imaging; Longitudinal; Prognosis; Stroke

Domaines: Imagerie médicale

Sharmila Sagnier, Gwenaëlle Catheline, Bixente Dilharreguy, Pierre-Antoine Linck, Pierrick Coupé, et al.. Normal-Appearing White Matter Deteriorates over the Year After an Ischemic Stroke and Is Associated with Global Cognition. Translational stroke research./Transl Stroke Res, 2022, ⟨10.1007/s12975-022-00988-8⟩. ⟨hal-03651487⟩