Lower plasma β-amyloid levels are associated with moderately greater rate of cognitive decline among older people without dementia
Are plasma β-amyloid (Aβ) levels associated with cognitive decline among older people without dementia?
Before exclusions, 3075 community-dwelling adults aged 70–79 years were recruited to the Health Aging and Body Composition (Health ABC study) in 1997–1998. They were selected from a random sample of people eligible for Medicare who were living in the study area. A subgroup of 997 adults with repeated cognitive testing and measurements of Aβ 40 and 42 was selected for analysis. Eligibility criteria: no difficulties with activities of daily living, able to walk a quarter mile or climb 10 steps without resting, free from life-threatening cancer and planning to remain within the study area for at least 3 years. Those with measurements were more likely to be female (55.2% of the study sample) of Black ethnicity (54.0%) and to have lower mean educational level compared with the rest of the cohort.
Community setting – Memphis, Tennessee, USA and Pittsburgh, Pennsylvania, USA – recruitment between 1997 and 1998.
Plasma levels of Aβ 42 and Aβ 40 levels. Plasma samples were stored at the first …