Brain volume loss precedes cognitive decline in the first year after ischaemic stroke. Issue 5 (8th May 2017) - Werden, Emilio
Abstract : Objectives: The aim of the current study was to examine trajectories of brain volume and cognition in ischaemic stroke patients in the first year after their events and compare results with age-matched controls. Methods: In the Cognition And Neocortical Volume After Stroke (CANVAS) study, we assessed ischaemic stroke patients within six weeks of their events and at 12 months post-stroke, and compared their results to healthy, age-matched controls. All participants were without dementia. Brain volume was assessed with high-resolution 3T MPRAGE MRI. FreeSurfer v5.1 was used to obtain total brain, hippocampal and thalamic volumes. The Hopkins Verbal Learning Test-Revised (HVLT-R) was used to assess memory, and the computerised Cogstate Battery was used to assess processing speed, working memory and attention. Results: Sixty-five stroke patients (51 male; age 65.98±11.6 years, education 12.71±3.9 years; baseline NIHSS 3.3±2.6; days post-stroke 26.83±9) and 38 controls (23 male; age 68.6±6.8; education 15.68±4.5 years) completed their assessments at baseline and 12 months. Oxfordshire classifications were PACI 31; POCI 25; LACI 9. Brain volumes were averaged across hemispheres for controls. Between baseline and 12 months, rates of decline in total brain volume, ipsilesional thalamic volume and ipsilesional hippocampal volume were significantly greater in stroke patients relative to controls (p<0.05). Contralateral brain volume loss in ischaemic stroke patients was not different to controls (p>0.05). Rates of cognitive decline over the same period were comparable between groups (p>0.05). Conclusions: Brain volume loss precedes cognitive decline in the first year after ischaemic stroke. Tracking brain volume after stroke is important because brain volume is predictive of cognitive decline and atrophy is a hallmark of dementia.