A recent study from UCLA Health suggests that a straightforward blood test might help doctors predict if someone is at a higher risk for stroke or cognitive decline in their lifetime. The study, which was published in the journal Stroke, discovered that by measuring levels of specific inflammatory molecules in the blood, doctors could determine a risk score for susceptibility to cerebral small vessel disease.Vessel disease, a common cause of stroke and cognitive decline, is often seen in the elderly. According to Dr. Jason Hinman of the UCLA Comprehensive Stroke and Center, currently the only way to assess someone’s risk for cerebral vascular diseases is through a combination of imaging such as an MRI scan, family history, demographic variables, and other risk factor evaluations. Neurologists may only identify a patient’s risk after they have experienced a stroke or a warning cerebral event.The new research discovered that by analyzing the levels of these inflammatory molecules in the blood of patients who have not experienced a cerebrovascular event, healthcare providers may be able to objectively assess a person’s likelihood of developing cerebral small vessel disease and having a stroke in the future. “Similar to how cholesterol tests are used to gauge future risk of a heart attack, we currently lack a method to estimate future risk of stroke,” Hinman explained. “I think we can accomplish that with something as straightforward as a blood test, which in theory can provide wider access to the highest level of care and not restrict it to advanced imaging studies.”In 2020, researchers conducted a study to investigate the interleukin-18 (IL-18) network, a biologically-connected network of inflammatory molecules that help fight infections. This network includes proteins and signaling molecules. Previous studies have found a connection between individual molecules in the IL-18 network and the risk of cerebral small vessel disease and stroke. However, the concentration of these molecules can vary due to other health conditions, such as the flu or autoimmune disorders, making them unreliable predictors of stroke risk at an individual level.Researchers at the University of California, including Hinman, discovered that six molecules in the IL-18 network were linked to the presence of vascular brain injuries shown on MRI scans.
Building on this discovery, Hinman wanted to investigate whether the IL-18 network could be used to evaluate an individual’s likelihood of experiencing a stroke or cognitive decline in their most recent publication.
The researchers utilized health data from the Framingham Heart Study, a long-term study that has been monitoring the medical histories of thousands of Framingham, Massachusetts residents over generations since it began.In 1948, blood samples were collected from participants and tested for five out of the six molecules that were later found to be part of the IL-18 network. The blood samples and medical histories of the Framingham participants were used by Hinman and his coauthor to develop a mathematical model. This model calculates a risk score based on the levels of the IL-18 network molecules. Hinman’s study included over 2,200 Framingham residents, and those whose risk scores were in the top 25% had an 84% chance of experiencing a stroke in their lifetime. In general, higher risk scores were linked to a 51% increased risk of stroke.The article discusses how a new tool for predicting stroke risk has shown promise compared to existing assessment tools. The article also mentions the need for further research on whether a person’s risk score can be lowered. The main focus is on preventing strokes before they occur, especially in the primary care setting.
