A groundbreaking study has provided genetic evidence linking damaged blood vessels in the brain to dementia and Alzheimer’s disease. This research focuses on white matter hyperintensity (WMH), a condition marked by brain lesions commonly associated with cerebral small-vessel disease. This disease involves the narrowing of blood vessels, obstructing blood flow and potentially causing strokes.
Cerebral small-vessel disease is a major contributor to cognitive decline and dementia, impairing memory and cognitive functions, which in turn affects daily living. Alzheimer’s disease is the most prevalent form of dementia.
The study, led by researchers at the University of Texas, highlights the previously limited “causal evidence” connecting WMH lesions to stroke and dementia. Although earlier studies indicated that these lesions, visible as bright areas on MRI brain scans, increased the risk of neurological deterioration, definitive genetic evidence was lacking.
Published in The Journal of the American Medical Association (JAMA) Network Open, the study presents genetic proof that vascular damage in the brain can lead to dementia. Researchers first estimated the genetic risk for developing WMH, stroke, and high blood pressure in individuals. Then, they compared these genetic risks to actual dementia cases, using data from population studies conducted between 1979 and 2018. The two-year analysis included up to 75,000 dementia cases of European ancestry.
Muralidharan Sargurupremraj, the study’s first author and an assistant professor at the University of Texas Health Sciences Center, emphasized the significance of their findings: “As vascular disease is a treatable contributor to dementia risk, our findings have broad significance for prevention strategies of Alzheimer’s and dementia as a whole.” With around 75 million people projected to develop dementia globally by 2030, the study’s authors underscore the urgency of devising strategies to prevent or delay its onset. They also suggest that future research should explore the applicability of their findings to non-European populations.
