Cross-sectional and longitudinal characterization of SCD patients recruited from the community versus from a memory clinic: subjective cognitive decline, psychoaffective factors, cognitive performances, and atrophy progression over time

Alzheimers Res Ther. 2019 Jul 8;11(1):61. doi: 10.1186/s13195-019-0514-z.


Background: Subjective cognitive decline (SCD) defines a heterogeneous population, part of which having Alzheimer's disease (AD). We aimed at characterizing SCD populations according to whether or not they referred to a memory clinic, by assessing the factors associated with increased AD risk.

Methods: Seventy-eight cognitively unimpaired older adults from the IMAP+ study (Caen) were included, amongst which 28 healthy controls (HC) and 50 SCD recruited from the community (SCD-community; n = 23) or from a memory clinic (SCD-clinic; n = 27). Participants underwent cognitive, psychoaffective, structural MRI, FDG-PET, and amyloid-PET assessments. They were followed up over a mean period of 2.4 ± 0.8 years. The groups were compared in terms of baseline and follow-up levels of SCD (self- and informant-reported), cognition, subclinical anxiety and depression, and atrophy progression over time. We also investigated SCD substrates within each SCD group through the correlations between self-reported SCD and other psychometric and brain measures.

Results: Compared to HC, both SCD groups showed similar cognitive performances but higher informant-reported SCD and anxiety. Compared to SCD-community, SCD-clinic showed higher informant-reported SCD, depression score, and atrophy progression over time but similar brain amyloid load. A significant increase over time was found for depression in the SCD-community and for self-reported praxis-domestic activities SCD factor in the SCD-clinic. Higher self-reported SCD correlated with (i) lower grey matter volume and higher anxiety in SCD-community, (ii) greater informant-reported SCD in SCD-clinic, and (iii) lower glucose metabolism in both SCD groups.

Conclusions: Higher subclinical depression and informant-reported SCD specifically characterize the SCD group that refers to a memory clinic. The same group appears as a frailer population than SCD-community as they show greater atrophy progression over time. Yet, both the SCD groups were quite similar otherwise including for brain amyloid load and the SCD-community showed increased depression score over time. Altogether, our findings highlight the relevance of assessing psychoaffective factors and informant-reported SCD in SCD populations and point to both differences and similarities in SCD populations referring or not to a memory clinic.

Trial registration: NCT01638949.

Keywords: Biomarkers; Neuroimaging; Pathological ageing; Preclinical Alzheimer’s disease; Psychoaffective factors; Subjective cognitive decline.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / diagnosis*
  • Alzheimer Disease / metabolism
  • Alzheimer Disease / pathology
  • Alzheimer Disease / physiopathology
  • Anxiety / diagnosis*
  • Biomarkers
  • Cognitive Dysfunction / diagnosis*
  • Cognitive Dysfunction / metabolism
  • Cognitive Dysfunction / pathology
  • Cognitive Dysfunction / physiopathology
  • Cross-Sectional Studies
  • Depression / diagnosis*
  • Diagnostic Self Evaluation*
  • Disease Progression*
  • Female
  • Follow-Up Studies
  • Gray Matter* / diagnostic imaging
  • Gray Matter* / metabolism
  • Gray Matter* / pathology
  • Gray Matter* / physiopathology
  • Humans
  • Longitudinal Studies
  • Magnetic Resonance Imaging
  • Male
  • Memory Disorders / diagnosis*
  • Memory Disorders / metabolism
  • Memory Disorders / pathology
  • Memory Disorders / physiopathology
  • Mental Status and Dementia Tests
  • Middle Aged
  • Neocortex* / diagnostic imaging
  • Neocortex* / metabolism
  • Neocortex* / pathology
  • Neocortex* / physiopathology
  • Positron-Emission Tomography
  • Prodromal Symptoms*


  • Biomarkers

Associated data