A lay summary written by Rachel Grasmeder Allen & reviewed by Dr Scott Allen.
A stroke occurs when a blood vessel in the brain either becomes blocked or bursts and bleeds. This blockage or bleed prevents blood and oxygen reaching parts of the brain. The result of this is damage to or death of these areas of the brain. The areas affected depend on which blood vessel is damaged. A transient ischaemic attack (TIA) is like a mini stroke: the blockage or bleed is temporary so the symptoms tend to be less severe. A common problem which occurs after a stroke or TIA is vascular dementia (dementia caused by damage to blood vessels in the brain). Vascular dementia occurs when there is restricted blood flow to the brain and results in symptoms such as memory problems, confusion and changes in mood. Stroke and dementia have many of the same risk factors, and having a stroke puts an individual at greater risk of having cognitive impairment (memory problems, problems with decision making and learning new things). There is currently not enough known about how many people experience post-stroke cognitive impairment (PSCI), and how PSCI progresses. The aim of this study is to determine the rates of PSCI and the risk factors for it, as well as looking at what might be causing PSCI with the hope of improving how PSCI is predicted in individuals.
This study plans to recruit at least 2000 participants from stroke centres across the UK. As of May 2020, 1416 participants had been recruited. Participants are being recruited within 6 weeks of having a stroke or TIA. They are being assessed when they first enrol in the study (at 24 hours to 6 weeks after having a stroke), again 4-8 weeks later and then again a minimum of 2 years later. The initial assessment involves collecting data including demographics (age, sex, race, religion), socioeconomic (occupation, education, wealth, where they live) and lifestyle factors (diet, smoking, alcohol, exercise), as well as clinical information about their stroke, recovery and symptoms. Brain scans are performed to assess where the stroke occurred in the brain and the severity of it, participants are asked about their pre-stroke cognition (how good they were at thinking and remembering) and blood is taken to be used in genetic tests. Genetic testing is being used because genetic factors can make people more likely to have a stroke and more likely to have Alzheimer’s disease, a type of dementia which commonly occurs in people with vascular dementia. At the two follow ups, participants are required to complete cognitive tests and their functional status is measured. This is their ability to complete normal daily tasks. Blood is also taken to test for inflammatory markers (proteins in the blood that indicate there is inflammation in the body). Inflammation is being measured as it has been found that certain inflammatory proteins are involved in cognitive decline including PSCI.
The major outcome of this study will be a measure of cognitive decline or dementia in participants up to at least two years post-stroke, in a broad range of participants. It will also record death, disability, disruption to normal daily function, impact on quality of life and the occurrence of any further strokes. It is hoped that the data from this study will increase our knowledge of PSCI, allowing improvements in the prediction and treatment of PSCI and vascular dementia to be made. Ultimately this should help to transform patient care by improving the diagnoses and outcomes of patients with stroke and vascular dementia.