Determinants of Cognitive Trajectories in Normal Aging : A Longitudinal PET-MRI Study in a Community-based Cohort

• Background: The determinants of the progressive decrement of cognition in normal aging are still a matter of debate. Alzheimer disease (AD)-signature markers and vascular lesions, but also psychological variables such as personality factors, are thought to have an impact on the longitudinal trajectories of neuropsychological performances in healthy elderly individuals.Objective: The current research aimed to identify the main determinants associated with cognitive trajectories in normal aging.Methods: We performed a 4.5-year longitudinal study in 90 older community-dwellers coupling two neuropsychological assessments, medial temporal atrophy (MTA), number of cerebral microbleeds (CMB), and white matter hyperintensities (WMH) at inclusion, visual rating of amyloid and FDG PET at follow-up, and APOE genotyping. Personality factors were assessed at baseline using the NEO-PIR. Univariate and backward stepwise regression models were built to explore the association between the continuous cognitive score (CCS) and both imaging and personality variables.Results: The number of strictly lobar CMB at baseline (4 or more) was related to a significant increase in the risk of cognitive decrement. In multivariable models, amyloid positivity was associated with a 1.73 unit decrease of the CCS at follow-up. MTA, WMH and abnormal FDG PET were not related to the cognitive outcome. Among personality factors, only higher agreeableness was related to better preservation of neuropsychological performances.Conclusion: CMB and amyloid positivity are the only imaging determinants of cognitive trajectories in this highly selected series of healthy controls. Among personality factors, higher agreeableness confers a modest but significant protection against the decline of cognitive performances.

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Geriatrik (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Geriatrics (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Radiologi och bildbehandling (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Radiology, Nuclear Medicine and Medical Imaging (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Neurologi (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Neurology (hsv//eng)

Keyword

Amyloid

atrophy

cognition

imaging markers

microbleeds

personality

Publication and Content Type

ref (subject category)

art (subject category)