A new study reveals that individuals with both hypertension and amyloid plaque accumulation are at a greater risk for cognitive impairment compared to those with only one of these risk factors. The findings were published on Wednesday in the journal Alzheimer’s & Dementia.
The research involved 467 participants from diverse racial backgrounds, with an average age of nearly 70. The study focused on two key factors associated with cognitive decline related to vascular issues and Alzheimer’s disease: white matter hyperintensity and amyloid plaques.
White matter hyperintensity indicates chronic microvascular disease, which researchers assessed using MRI scans. “White matter hyperintensity appears as extra white in the brain’s white matter during MRI scans. It reflects neuron scarring, which we often observe in autopsies of individuals with vascular dementia,” explained Adam de Havenon, an associate professor of neurology at Yale School of Medicine and the study’s lead author.
To measure amyloid plaque buildup, the researchers analyzed blood samples for the ratio of two peptides linked to amyloid beta accumulation, a known biomarker for Alzheimer’s disease.
The team evaluated participants at the beginning of the study and again over an average follow-up period of 4.8 years to assess their risk levels for brain scarring and amyloid buildup. The results showed that individuals at high risk for both conditions had nearly a fivefold increase in the likelihood of developing cognitive impairment during the follow-up. Conversely, those with the lowest risk scores for both factors exhibited the least cognitive impairment.
“We discovered that participants with greater white matter hyperintensity and higher amyloid-beta levels had a significantly increased risk of cognitive impairment compared to those with only one of these factors,” de Havenon stated.
The researchers emphasized the need for clinical trials aimed at treating both hypertension and amyloid buildup. “This is a health equity issue,” de Havenon said. “We must conduct trials that address both amyloid and hypertension. This approach is essential to reduce the growing health disparities in dementia.”