Awareness and Its Association With Affective Symptoms in Young-onset and Late-onset Alzheimer Disease: A Prospective Study

Background: It is unknown whether there are differences between young-onset dementia and late-onset dementia in awareness levels and whether awareness is differentially associated with affective symptoms in both groups. The present study assesses possible differences between young-onset (YO-AD) and late-onset Alzheimer disease (LO-AD) in awareness levels and the association between awareness and affective symptoms.Methods: This study included 142 YO-AD and 126 LO-AD patients and their caregivers from 2 prospective studies. The participants were assessed 3 times during 1 year. Awareness was assessed using the Guidelines for the Rating of Awareness Deficits, and affective symptoms were assessed using the anxiety and depression items of the Neuropsychiatric Inventory. Population-averaged logistic regressions were used to analyze awareness and its association with affective symptoms.Results: The odds for impaired awareness in LO-AD were more than double the odds in YO-AD. Intact awareness was associated with depressive symptoms but not with anxiety. This effect was more pronounced in YO-AD compared with LO-AD at baseline. High awareness at baseline did not predict incident affective symptoms.Conclusions: Caregivers and clinicians should be prepared for affective symptoms in YO-AD patients with high awareness. The higher awareness in the YO-AD group also has potential positive implications for this group.