Study Examines the Role of Vascular Disease in Alzheimer Risk

The presence of vascular risk factors during middle age is associated with elevated brain amyloid deposition in later life, strengthening the evidence of a role for vascular disease in Alzheimer disease development, according to a new study.

While midlife vascular risk factors have been associated with later-life dementia, their effects on brain amyloid deposition is less well defined.

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The researchers conducted a prospective cohort study of 322 participants without dementia who had been evaluated for vascular risk factors since 1987 to 1989 and then underwent positron emission tomography to measure brain amyloid from 2011 to 2013. The researchers defined vascular risk factors as obesity, current smoking, hypertension, diabetes, and elevated total cholesterol.

At baseline, 65 participants had no vascular risk factors, 123 had 1 risk factor, and 134 had 2 or more risk factors. Overall, elevated body mass index in midlife, as well as a higher number of midlife risk factors, were both associated with increased brain amyloid deposition later in life. Compared with having no midlife vascular risk factors, the odds ratio for elevated amyloid deposition was 1.88 in those with 1 risk factor and 2.88 in those with 2 or more risk factors.

“In a prospective cohort study of 346 members of the community-based Atherosclerosis Risk in Communities (ARIC)–PET cohort without dementia, having 2 or more midlife vascular risk factors compared with none was significantly associated with elevated amyloid deposition in the brain (61.2% vs 30.8%). There was no significant association for late-life risk factors,” the researchers concluded.

—Michael Potts

Reference:

Gottesman RF, Schneider ALC, Zhou Y, et al. Association between midlife vascular risk factors and estimated brain amyloid deposition. JAMA. 2017;317(14):1443-1450.