Introduction: Subjective cognitive decline (SCD) could help identify early stages of Alzheimer's disease. However, SCD is multidetermined and protean, and the type of cognitive complaint associated with preclinical Alzheimer's disease needs refinement.
Methods: A total of 185 nondemented elders recruited from either the community or from a memory clinic filled a questionnaire. We searched for item responses associated with medical help seeking, cognitive deficits, and β-amyloidosis.
Results: Compared with community-recruited control subjects (n = 74), help-seeking patients reported a stronger multidomain SCD that was mostly unrelated to the presence of detectable cognitive deficits. Only a few items, notably assessing temporal disorientation, distinguished help-seeking patients with (n = 78) or without (n = 33) memory deficits. Associations between SCD and β-amyloidosis were not restricted to the memory domain and varied across clinical stages.
Discussion: Detailed evaluation of SCD could provide accessible indication of the presence of β-amyloid or cognitive deficits, which might prove useful for early diagnosis and clinical trial enrichment strategies.
Keywords: Anosognosia; Biomarkers; Memory complaint; Mild cognitive impairment; Orientation; Positron emission tomography; Preclinical; Prodromal Alzheimer's disease; Subjective cognitive decline; β-Amyloid.