Time Trend in Persistent Cognitive Decline: Results From the Longitudinal Aging Study Amsterdam

Area of Science:

• Gerontology
• Neuroscience
• Epidemiology

Background:

• Persistent cognitive decline (PCD) is a growing concern in aging populations.
• Understanding temporal trends in PCD incidence is crucial for public health planning.
• The role of established dementia risk factors in explaining these trends requires investigation.

Purpose of the Study:

• To examine time trends in the incidence of persistent cognitive decline (PCD) among older adults.
• To determine if changes in well-known dementia risk factors explain observed trends in PCD incidence.

Main Methods:

• Utilized 20-year data from the Longitudinal Aging Study Amsterdam.
• Assessed within-person cognitive change to identify PCD in 65-88 year-olds across 7 waves.
• Employed logistic generalized estimating equations (GEE) with time as the primary predictor of 3-year PCD incidence.

Main Results:

• PCD incidence rose from 2.5% to 3.4% over the study period.
• A significant positive time trend for PCD incidence was observed (Exp(B)time = 1.042, p < .001).
• Higher age, lower education, diabetes, smoking, lower BMI, and physical inactivity were associated with increased PCD incidence, but did not explain the time trend.

Conclusions:

• A notable increase in PCD incidence over two decades was identified.
• Established dementia risk factors, while independently associated with PCD, did not account for the observed rise in incidence over time.