People with hypertension and amyloid plaque buildup may have a higher risk of cognitive impairment compared with those who have only one risk factor, a study finds.
The study was published Wednesday in Alzheimer’s & Dementia.
Data came from 467 racially diverse participants with an average age of nearly 70.
Investigators looked at the presence of two factors related to impairments that result from vascular issues and Alzheimer’s disease: white matter hyperintensity and plaque amyloid.
White matter hyperintensity reflects chronic microvascular disease. Researchers used MRI to evaluate it.
“White matter hyperintensity means that when we look at the brain via MRI, the white matter, or the nerve connections between different regions of the brain, shows up as extra white,” Adam de Havenon, an associate professor of neurology at Yale School of Medicine and lead author, said in a statement. “We see it as scarring of the neurons when we look at the brain during autopsies of individuals who had vascular dementia.”
The team also measured amyloid plaque buildup by measuring the ratio of two peptides in the blood that are linked to amyloid beta buildup in the brain — a biomarker for Alzheimer’s disease.
The researchers determined which participants were at low and high risk for brain scarring and amyloid buildup during baseline testing, and then again over the course of 4.8 years.
People with high risk for both white matter hyperintensity and blood biomarkers had a nearly fivefold increase in risk of cognitive impairment during the follow-up period. Those with the lowest risk scores for both metrics had the lowest rate of cognitive impairment.
“We found that the risk of developing cognitive impairment was considerably higher for the participants who had more white matter hyperintensity and more amyloid-beta than for those who just had one or the other,” de Havenon said.
The team called for clinical trials to determine how to treat both risk factors.
“This is a health equity issue,” de Havenon said. “We have to conduct trials that look at treating both amyloid and hypertension. It’s the only way we can avert the growing health disparities in dementia.”
