Supplemental Materials Eikelboom et al. Neuropsychiatric and cognitive symptoms across the Alzheimer's disease clinical spectrum

The objective of this study was to investigate the prevalence and trajectories of neuropsychiatric symptoms (NPS) in relation to cognitive functioning in a cohort of amyloid-β positive individuals across the Alzheimer’s disease (AD) clinical spectrum. In this single-center observational study, we included all individuals who visited the Alzheimer Center Amsterdam and had 1) a clinical diagnosis of subjective cognitive decline (SCD), mild cognitive impairment (MCI), or probable AD dementia, and 2) were amyloid-β positive (A+). We measured NPS with the Neuropsychiatric Inventory (NPI), examining total scores and the presence of specific NPI domains. Cognition was assessed across five cognitive domains and with the MMSE. We examined trajectories including model based trends for NPS and cognitive functioning over time. We used linear mixed models to relate baseline NPI scores to cognitive functioning at baseline (whole-sample) and longitudinal time-points (subsample n=520, Mean=1.8 [SD=0.7]...