Grant: Project Grant

Stroke happens when blood flow to the brain is blocked, and can cause problems with memory and thinking. These problems can happen even when people recover from symptoms like weakness or speech problems. This means there are other factors at play that worsen memory after stroke. Signs of age or damage built up in the brain- like shrinkage and problems with small vessels - are called "brain frailty" and may affect how the brain handles a stroke. However, stroke treatment studies have mostly ignored these signs. The ABACUS project will study how different signs of brain frailty are connected to memory and thinking problems after stroke. We will bring together 10 datasets that have collected brain scans and tested people's thinking abilities after different types of stroke. These include over 5,100 patients with large strokes, mini-strokes, and strokes happening after surgeries. We will have similar information from more than 1,500 people without strokes to compare. We will study the brain scans in detail and look for signs of brain frailty like shrinkage, patchy damage to white matter, old strokes, and bleeding spots. We will also assess damage caused by the new stroke. We will analyze whether signs of brain frailty worsen memory and thinking beyond what is explained by things like the stroke's size and treatments received. We will identify which brain frailty signs are most important for predicting these problems. We will combine these signs into an ABACUS Brain Frailty Score that can be easily used by doctors and researchers. We will also build machine-learning models to predict the risk of memory/thinking problems in a personalized way. We will share our findings with patients, caregivers, doctors, and researchers. The goal is to help doctors give better advice or predictions to patients about their risk of memory problems after stroke. Our work will also help researchers pay more attention to brain frailty when testing treatments to prevent such memory problems.