Association of Performance on the Financial Capacity Instrument–Short Form With Brain Amyloid Load and Cortical Thickness in Older Adults

Background and Objectives To investigate the association of the Financial Capacity Instrument–Short Form (FCI-SF) performance and timing total scores with brain β-amyloid and cortical thickness in cognitively unimpaired (CU) (at baseline) older adults.

Methods A total of 309 participants (aged 70 years or older) of the Mayo Clinic Study of Aging underwent ¹¹C-Pittsburgh compound B PET amyloid imaging and MRI, and completed the FCI-SF. Abnormal amyloid PET was defined as standardized uptake value ratio ≥1.48 in an Alzheimer disease (AD)-related region of interest and reduced AD signature cortical thickness as ≤2.68 mm (neurodegeneration). A cohort of 218 (of the 309) participants had follow-up visits (every 15 months) with FCI-SF data for longitudinal analysis (number of visits including baseline, median [range]: 2 [2–4]). In the analysis, we used linear regression and mixed-effects models adjusted for age, sex, education, apolipoprotein E ε4 allele status, global cognitive z score, and previous FCI-SF testing.

Results Participants' mean age (SD) was 80.2 (4.8) years (56.3% male individuals). In cross-sectional analysis, abnormal amyloid PET (vs normal) was associated with a lower FCI-SF total score and slower total composite time. In longitudinal analysis, FCI-SF total score declined faster (difference in annualized rate of change, beta coefficient [β] [95% confidence interval (CI)] = −1.123 [−2.086 to −0.161]) and FCI-SF total composite time increased faster (difference in annualized rate of change, β [95% CI] = 16.274 [5.951 to 26.597]) for participants with neurodegeneration at baseline (vs those without). Participants who exhibited both abnormal amyloid PET and neurodegeneration at baseline had a greater increase in total composite time when compared with the group without abnormal amyloid and without neurodegeneration (difference in annualized rate of change, β [95% CI] = 16.750 [3.193 to 30.307]).

Discussion Performance and processing speed on the FCI-SF were associated with imaging biomarkers of AD pathophysiology in CU (at baseline) older adults. Higher burdens of imaging biomarkers were associated with longitudinal worsening on FCI-SF performance. Additional research is needed to delineate further these associations and their predictive utility at the individual person level.