Confabulations in remembering past and planning future are associated with psychiatric symptoms in Alzheimer's disease.

Psychiatric symptoms such as delusions and aggression are frequently observed in patients with Alzheimer's disease (AD), but few studies examined the association of these symptoms with confabulations. We studied 32 AD patients and 10 age- and education-matched healthy older adults. The AD patients were divided into delusion/aggression and non-delusion/non-aggression groups based on their behavioral pathology in AD frequency-weighted severity scale score. Confabulations were assessed using questions about temporality (personal past, orientation, and future planning), and cognitive functions were determined using the mini-mental state examination and the cognitive abilities screening instrument. The AD patients showed confabulations on all types of questions, and their confabulation scores for the past and future were strongly correlated. Cognitive functions were not significantly correlated with confabulation scores for any type of questions. The delusion/aggression group had significantly more confabulations on past and future questions compared to the non-delusion/non-aggression group. These findings suggested that confabulations in remembering the past and planning the future were affected by psychiatric symptoms such as delusion and aggression.