The trajectory of delusions in patients with Alzheimer's disease receiving pharmacological treatment: A re-analysis of data from the CATIE-AD trial.

Abstract

Background: Previous studies have reported decreases in the proportion of patients with delusions and severity of delusions during long-term follow-up in Alzheimer's disease (AD).

Objective: The aim of the present study was to explore clinical predictors of the disappearance of delusions in AD patients enrolled in the Clinical Antipsychotic Trials of Intervention Effectiveness-Alzheimer's Disease (CATIE-AD) trial who received pharmacological treatment.

Methods: We re-analyzed the data of 421 clinic-based patients enrolled in the CATIE-AD trial to examine the association between the disappearance of delusions and relevant factors selected by reference to previous studies at week 12, 24, and 36 of treatment. Generalized Estimating Equations were used to analyze the impact of the assigned medication (mainly atypical antipsychotics), treatment duration, and their interaction on the disappearance of delusions over time.

Results: The proportion of patients with delusions (PWD) gradually decreased to approximately 50% over the 36-week treatment period; however, no significant differences in the baseline variables were identified between the PWD and patients without delusions (POD) at any of the follow-up time-points (weeks 12, 24, or 36). Furthermore, the treatment duration was found to contribute significantly to the disappearance of delusions over time (conversion from PWD at baseline to POD at subsequent follow-up visits), independent of active drug use.

Conclusions: Disappearance of delusions in AD patients was associated with the interval from the baseline, regardless of the use of active drugs. Insights into the natural course of delusions could guide clinicians toward selecting alternative treatment strategies for patients with AD.