Change in Cognition Following Ischaemic Stroke.

OBJECTIVE

Cognitive decline can occur following ischaemic stroke. How cognition changes over time and associations with cognitive change are poorly understood. This study aimed to explore these issues over 2 years following ischaemic stroke.

METHODS

This analysis used data from the XILO-FIST study, a clinical trial of allopurinol versus placebo in people with ischaemic stroke according to Tissue-Based Definition. Participants underwent clinical assessment, brain MRI at baseline, and Montreal Cognitive Assessment (MoCA) at baseline, year 1 and year 2. We defined cognitive impairment as a MoCA score < 26 and cognitive change as a difference in MoCA score of 2 points or more at year 1 or year 2 after randomisation. Associations with cognitive impairment and cognitive change were assessed by univariable analysis and multiple logistic regression.

RESULTS

Three hundred and sixty participants with complete MoCA data were included. Mean age was 65.4 (SD 8.36) years, and mean baseline MoCA score was 26.4 (SD 2.7). Seventy-seven participants had second-year cognitive improvement. Eighty-four had second-year cognitive decline. After adjustment for age and education year, second-year cognitive improvement was associated with smaller brain volume, lower albumin level, smoking and greater white-matter hyperintensity, and second-year cognitive decline was associated with peripheral arterial disease, higher cholesterol level, small-vessel stroke and greater white-matter hyperintensity.

INTERPRETATION: Cognition is dynamic following stroke, with different patterns of change. Brain reserve and vascular risk factors relate to later post-stroke cognitive change. This complex nature of cognitive trajectory has implications for cognitive rehabilitation provision and cognitive impairment detection after stroke.