Characteristics of Subjective Cognitive Decline Associated with Alzheimer's Disease Amyloid Pathology: Findings from The CABLE Study

Background: Subjective cognitive decline (SCD) is considered as a preclinical hallmark of Alzheimer's disease (AD). However, the characteristics of SCD associated with amyloid pathology remain unclear. Objective: We aimed to explore the associations between SCD characteristics with amyloid pathology. Methods: Using logistic regression analyses, we analyzed the associations between cerebrospinal fluid (CSF) amyloid pathology with AD risk factors, SCD-specific characteristics (onset of SCD within the last five years, age at onset =60 years, feelings of worse performance, informant confirmation of complaints, worries, other domains of cognition complaints), as well as subthreshold depressive and anxiety symptoms among individuals with SCD. Results: A total of 535 SCD individuals with available CSF A beta(42) information from the Chinese Alzheimer's Biomarker and LifestylE (CABLE) study (mean age of 63.5 years, range 40 to 88 years; 47.10% female) were enrolled. The characteristics of informant confirmation of complaints (OR, 95% CI = 2.00, 1.19-3.36), subthreshold depressive symptoms (OR, 95% CI = 2.31, 1.05-5.09), and subthreshold anxiety symptoms (OR, 95% CI = 2.22, 1.09-4.51) were found to be significantly associated with pathological amyloid in multivariate analyses when adjusting for age, sex, education, and APOE epsilon 4. Besides, age and females were observed risks for amyloid pathology in subscale analyses. Nonetheless, we did not find any associations of other SCD-specific characteristics with amyloid pathology in this study. Conclusion: Our study suggested that informant confirmed complaints and subthreshold psychiatric symptoms might be critical for discriminating AD-related SCD from non-AD related SCD.