The Diagnostic Landscape of Behavioral Variant Frontotemporal Dementia.

The behavioral variant of frontotemporal dementia (bvFTD) is a progressive, neurodegenerative disorder, characterized by profound changes in personality, behavior, and social comportment. Diagnosis of bvFTD is challenging, and it is frequently misdiagnosed as an idiopathic psychiatric disorder (e.g., major depressive disorder, bipolar disorder) or another neurodegenerative disease (e.g., Alzheimer's disease dementia). The diagnostic challenge is exacerbated by a lack of reliable in vivo biological markers of disease pathology, which means that, at present, diagnosis relies largely on detailed behavioral and cognitive assessments. In this article, we discuss how clinical diagnostic criteria for bvFTD have evolved over the past three decades, and emphasize the diagnostic uncertainty that can arise when trying to distinguish between bvFTD and primary psychiatric disorders or other neurodegenerative diseases. In highlighting the strengths and limitations of the revised diagnostic criteria, and taking into account current diagnostic predicaments, we provide evidence-based recommendations for clinicians facing this diagnostic question. Finally, we touch on the importance of early (i.e., prodromal) diagnosis, and explain the utility of biomarkers for bvFTD diagnosis, with a nod to exciting research developments in this area.