Severity of subjective cognitive complaints and worries in older adults are associated with cerebral amyloid‐β load: Neuropsychology/Neuropsychological correlates of physiologic markers of cognitive decline/Dementia. (7th December 2020) - Schwarz, Claudia
Abstract: Background: Subjective cognitive decline (SCD) is considered an early risk stage for the development of Alzheimer's disease (AD) and pathological brain alterations, including the aggregation of amyloid‐β plaques (Jessen et al., Alzheimer's & Dementia 2014). This prospective study evaluates the association between specific features of SCD, including severity of subjective cognitive complaints and trait worry, and regional cerebral amyloid‐β load in cognitively normal older individuals. Method: Cerebral amyloid‐β load was assessed by positron emission tomography with 18F‐florbetaben in 30 individuals with SCD (age 67 ± 4 years) at baseline in an ongoing interventional study (clinicaltrial.gov: NCT03094546) and in 10 healthy older adults (age 72 ± 8 years) following the same baseline protocol. Regional amyloid‐β load was quantified for frontal, temporal, parietal, and cingulate cortex using whole cerebellum as reference. Subjective complaints regarding different cognitive domains (memory, language, visuospatial abilities, planning, organization, and divided attention) were determined using the 39‐item Everyday Cognition Scales. Trait evaluation of pathological worry was captured by the self‐reported 16‐item Penn State Worry Questionnaire. Associations between specific features of SCD and cerebral amyloid‐β load were tested by age‐adjusted Spearman rank partial correlation analyses, uncorrected for multiple testing. Result: Across all participants, severity of subjective cognitive complaints regarding memory, organization, and divided attention was positively correlated with amyloid‐β load in the frontal cortex (p = .008, .018, .024, respectively). Severity of subjective cognitive complaints regarding planning was positively correlated with amyloid‐β load in the parietal cortex (p = .025). Higher trait level of pathological worry was associated with higher amyloid‐β load in the frontal cortex (p = .031). Conclusion: In cognitively normal older individuals, severity of subjective cognitive complaints and level of trait worry are positively associated with cortical amyloid‐β burden, particularly in the frontal cortex. This region is considered a core region of the default mode network that is affected early in AD (Palmqvist et al., Nature Communications 2017). Interventions aiming to reduce rumination and worries may help prevent amyloid deposition in these regions, a hypothesis to be tested in future interventional trials.