Plasma amyloid-? and risk of Alzheimer's disease in the Framingham Heart Study.

ABSTRACT: BACKGROUND:Plasma amyloid-? (A?) peptide levels have been examined as a low-cost accessible marker for risk of incident Alzheimer's disease (AD) and dementia, but results have varied between studies. We reassessed these associations in one of the largest, prospective, community-based studies to date. METHODS:A total of 2189 dementia-free, Framingham Study participants aged >60 years (mean age, 72 ± 8 years; 56% women) had plasma A?1-42 and A?1-40 measured and were followed prospectively (mean, 7.6 ± 3.0 years) for dementia/AD. RESULTS:Increased plasma A?1-42 levels were associated with lower risk of dementia (A?1-42: hazard ratio [HR] = 0.80 [0.71?0.90], P < .001; A?1-42-to-A?1-40 ratio: HR = 0.86 [0.76?0.98], P = .027) and AD (A?1-42: HR = 0.79 [0.69?0.90], P < .001; A?1-42-to-A?1-40 ratio: HR = 0.83 [0.72?0.96], P = .012). CONCLUSION:Our results suggest that lower plasma A? levels are associated with risk of incident AD and dementia. They encourage further evaluation of plasma A? levels as a biomarker for risk of developing clinical AD and dementia.

SUBMITTER: Chouraki V 

PROVIDER: S-EPMC4362883 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature