Changes in self- and study partner-perceived cognitive functioning in relation to amyloid status and future clinical progression: Findings from the SCIENCe project.

Abstract

We investigated changes in self- and study partner-reported self-perceived cognitive decline in relation to amyloid pathology and clinical progression, in a sample of cognitively normal individuals. A total of 404 participants (63±9 years, 44% female) and their study partners completed the Cognitive Change Index (CCI) yearly (0.7-6.8 follow-up years; n visits=1436). Baseline and longitudinal associations between (change in) CCI scores, amyloid, and clinical progression were modeled in linear mixed models and Cox regressions. CCI-study partner scores of amyloid-positive individuals increased over time (B=1.79, 95% confidence interval [CI]=[0.51, 3.06]), while CCI-self scores remained stable (B=-0.45, 95% CI=[-1.77, 0.87]). Ten-point higher baseline CCI-study partner (hazard ratio [HR]=1.75, 95% CI=[1.30, 2.36]) and CCI-self scores (HR=1.90, 95% CI=[1.40, 2.58]) were associated with an approximately 2-fold increased risk of progression to mild cognitive impairment or dementia. Study partner-reported but not self-perceived complaints increase over time in amyloid-positive individuals, supporting the value of longitudinal study partner report, even in initially cognitively normal individuals.