Subjective cognitive decline and rates of incident Alzheimer's disease and non-Alzheimer's disease dementia

Alzheimers Dement. 2019 Mar;15(3):465-476. doi: 10.1016/j.jalz.2018.10.003. Epub 2018 Dec 13.


Introduction: In this multicenter study on subjective cognitive decline (SCD) in community-based and memory clinic settings, we assessed the (1) incidence of Alzheimer's disease (AD) and non-AD dementia and (2) determinants of progression to dementia.

Methods: Eleven cohorts provided 2978 participants with SCD and 1391 controls. We estimated dementia incidence and identified risk factors using Cox proportional hazards models.

Results: In SCD, incidence of dementia was 17.7 (95% Poisson confidence interval 15.2-20.3)/1000 person-years (AD: 11.5 [9.6-13.7], non-AD: 6.1 [4.7-7.7]), compared with 14.2 (11.3-17.6) in controls (AD: 10.1 [7.7-13.0], non-AD: 4.1 [2.6-6.0]). The risk of dementia was strongly increased in SCD in a memory clinic setting but less so in a community-based setting. In addition, higher age (hazard ratio 1.1 [95% confidence interval 1.1-1.1]), lower Mini-Mental State Examination (0.7 [0.66-0.8]), and apolipoprotein E ε4 (1.8 [1.3-2.5]) increased the risk of dementia.

Discussion: SCD can precede both AD and non-AD dementia. Despite their younger age, individuals with SCD in a memory clinic setting have a higher risk of dementia than those in community-based cohorts.

Keywords: Alzheimer's disease; Dementia Lewy bodies; Dementia incidence; Frontotemporal dementia; Preclinical Alzheimer's disease; Subjective cognitive decline; Vascular dementia.

Publication types

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

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cognitive Dysfunction / epidemiology*
  • Cognitive Dysfunction / psychology
  • Cohort Studies
  • Dementia / epidemiology*
  • Dementia / psychology
  • Diagnostic Self Evaluation
  • Disease Progression
  • Female
  • Humans
  • Incidence
  • Male
  • Middle Aged
  • Risk Factors
  • Self Concept