Behavioral dimensions and acetylcholinesterase inhibitor-related effect in Alzheimer disease over time: a latent trajectory modeling.

ABSTRACT

OBJECTIVE: To evaluate whether treatment with acetylcholinesterase inhibitors (AChEIs) exerts a favorable effect on the behavioral dimensions in Alzheimer disease (AD) over time. METHODS: Two hundred AD patients entered the study and underwent clinical and neuropsychologic examination. Neuropsychiatry Inventory (NPI) total scores and 4 behavioral factor scores, termed "psychosis," "moods," "apathy," and "frontal" were also evaluated. Of this large sample, 107 completed the 6-month follow-up and 83 were followed through for 1 year. Latent Trajectory Modeling analysis was applied, which allows for the estimation of a developmental trajectory over time for each case in the sample adjusting for confounders. These trajectories can be modeled to better understand individual differences in rates of change of behavioral dimensions and the relationship with AChEIs dose therapy. RESULTS: The behavioral phenotypes and NPI total scores were differently expressed, the most prevalent being the mood and the less prevalent being frontal endophenotype over time. The development relationship between the baseline and trend levels of behavioral phenotypes, or NPI total scores and the differences of AChEIs, adjusting for disease severity, concurrent drugs, and demographic data did not "travel together" through time, that is, the correlations of individual trajectories could be estimated equal to zeros. CONCLUSIONS: These data confirm that behavioral dimensions are variably represented in AD and change over time. However, AChEIs could not influence the behavioral disturbance pattern, both measured as total behavioral abnormality burden or as behavioral defined clusters.