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

J Gerontol B Psychol Sci Soc Sci. 2018 Apr 16;73(suppl_1):S57-S64. doi: 10.1093/geronb/gbx151.

Abstract

Objective: To study time trends in the incidence of persistent cognitive decline (PCD), and whether an increase or decrease is explained by changes in well-known risk factors of dementia.

Method: Data from the Longitudinal Aging Study Amsterdam over a period of 20 years were used. Subsamples of 65-88 year-olds were selected at 7 waves, with numbers ranging from 1,800 to 1,165. Within-person change in cognitive functioning was used to determine PCD. In logistic generalized estimating equations (GEE), time (0, 3, 6, 9, 13, and 16 years) was the main predictor of 3-year PCD incidence. Explanatory variables were lagged one wave before incident PCD and included in separate models.

Results: PCD incidence was 2.5% at first, and 3.4% at last follow-up. GEE showed a positive time trend for PCD incidence [Exp(B)time = 1.042; p < .001]. None of the explanatory variables significantly changed the strength of the regression coefficient of linear time. Higher age, lower education, diabetes mellitus, smoking, lower body-mass index, and lower level of physical activity were associated with higher incidence of PCD.

Conclusion: An increase in PCD incidence over time was found. Although well-known risk factors were associated with incidence per se, they did not explain the increase in incidence of PCD.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Aging*
  • Cognitive Dysfunction / epidemiology*
  • Dementia / epidemiology
  • Disease Progression
  • Female
  • Humans
  • Incidence
  • Longitudinal Studies
  • Male
  • Netherlands / epidemiology
  • Risk Assessment
  • Risk Factors
  • Severity of Illness Index*
  • Time Factors