Mood Changes in Cognitively Normal Older Adults are Linked to Alzheimer Disease Biomarker Levels

Abstract

To evaluate whether cerebrospinal fluid (CSF) and PET Pittsburgh Compound B (PiB) biomarkers of underlying Alzheimer disease (AD) pathology (β-amyloid42 [Aβ42], tau, phosphorylated tau181 [ptau181], tau/Aβ42, ptau181/Aβ42 and mean cortical binding potential [MCBP] for PET-PiB) predict changes in mood in cognitively normal older adults. Knight Alzheimer's Disease Research Center (ADRC) at Washington University (WU). Participants, 65 years of age or older, were enrolled from longitudinal studies at the WU Knight ADRC. CSF, PET-PiB biomarkers, Clinical Dementia Rating (CDR), Mini-Mental State Examination (MMSE), Profile of Mood States-Short Form (POMS-SF), the Geriatric Depression Scale (GDS), and Neuropsychiatric Inventory Questionnaire (NPI-Q). Data from 118 participants at baseline and 66 participants at one-year follow-up were analyzed. CSF and PET biomarkers were not associated cross-sectionally with any mood disturbances at baseline (p > 0.05). Changes in mood as indicated by the total mood disturbance score on the POMS-SF, selected POMS-SF subscales, GDS, and NPI-Q scores from baseline to one-year follow-up were associated with (p < 0.05) CSF and PET-PiB biomarkers. There was no statistically significant decline in cognitive functioning. Generally, higher values of CSF and PET-PiB biomarkers are associated with more changes in mood in cognitively normal older adults. Further work is needed to understand the temporal development of mood changes over several years during the phase of preclinical AD. Evaluating mood as a noncognitive outcome may provide further insight into the development of preclinical AD in cognitively normal older adults.