Alzheimer’s disease (AD) is a heterogeneous disease, with the behavioral variant being rare. This behavioral variant of Alzheimer’s disease (bvAD) is characterized by early and predominant behavioral deficits and personality changes caused by AD pathology. The challenge of clinically diagnosis lies in the fact that the bvAD clinical syndrome overlaps substantially with that of the behavioral variant of frontotemporal dementia (bvFTD). Therefore, to better understand the bvAD phenotype, researchers of the Alzheimer Center Amsterdam performed a systematic review and meta-analysis of the clinical neuroimaging, and neuropathology bvAD literature and applied the outcomes to develop research criteria for bvAD.
Ossenkoppele and his colleagues included studies reporting on behavioral, neuropsychological, or neuroimaging features in bvAD. When available, they included the provided comparisons with typical AD or bvFTD. In the end, 83 studies were included, with 13 suitable for meta-analysis. The review showed that, at the time of diagnosis, bvAD showed more severe neuropsychiatric symptoms and other behavioral deficits compared to typical AD. The neuroimaging literature revealed two bvAD phenotypes: one with an AD-like pattern and one with a relatively more bvFTD-like pattern. The AD-like patterns however are more prevalent.
First research criteria
Overall, this analysis showed that bvAD is clinically most like bvFTD, while sharing more pathophysiological features with typical AD. Based on these insights, they provide the first research criteria for bvAD, aiming to improve the consistency and reliability of future research and potentially facilitate the clinical assessment.
Read the publication in JAMA Neurology: Research Criteria for the Behavioral Variant of Alzheimer Disease