Alzheimer’s Research & Therapy (Oct 2020)

Trajectories of subjective cognitive decline, and the risk of mild cognitive impairment and dementia

  • Tau Ming Liew

DOI
https://doi.org/10.1186/s13195-020-00699-y
Journal volume & issue
Vol. 12, no. 1
pp. 1 – 12

Abstract

Read online

Abstract Background In cognitively normal individuals, subjective cognitive decline (SCD) has been reported to predict MCI and dementia (MCI/dementia). However, prior studies mostly captured SCD at single time-points without considering the longitudinal course of SCD. This study examined whether the trajectories of SCD provide any added information—beyond one-time assessments of SCD—on the risk of MCI/dementia. Methods This cohort study included 5661 participants from the Alzheimer’s Disease Centers across the USA, who were ≥ 50 years and had normal cognition in the first-four annual visits (year 1 to year 4). The participants were evaluated for SCD in the first-four annual visits (year 1 to year 4), and followed-up almost annually (year 4 up to year 14) for incident MCI/dementia. SCD trajectories (as identified from latent-class-growth-curve-analysis) were included in Cox regression to estimate their risks of MCI/dementia, with analyses further stratified by age ( 75% probability of developing MCI/dementia by 10 years, in contrast to < 25% probability by 10 years in younger individuals with No SCD. Conclusions The findings demonstrate the utility of SCD trajectories—especially when used in combination with age strata—in identifying high-risk populations for preventive interventions and trials. They also suggest a potential modification in the current SCD criteria, with the inclusion of “persistent SCD over several years” as a feature of SCD plus.

Keywords