Neuropsychiatric Characteristics of Alzheimer's Disease and the Behavioral Variant of Frontotemporal Dementia

Neurodegenerative dementias that occur in adults can present with significant behavioral symptoms in addition to the cognitive syndrome. These can be disruptive for the families who take care for these patients and cause a significant burden on the medical system. The incidence of Alzheimer’s disease (AD) is frequently greater in patients over 65 years of age, whereas the behavioral variant of frontotemporal dementia (bvFTD) is more common in subjects younger than 65. All the same, AD can have an early onset and present with behavioral symptoms that resemble bvFTD. Similarly, bvFTD can begin after age 65, thereby mimicking an AD syndrome. Whereas an amnesic syndrome along with deterioration in other cognitive domains, mood-related symptoms, psychosis and functional disabilities are the main elements characterizing AD, a dysexecutive syndrome accompanied by other neuropsychological detriments, a profound lack of social cognition and functional deterioration are the most prominent signs suggesting the presence of bvFTD. It should be noted, however, that in some cases, especially those in which AD begins before age 65, clinical differentiation of the two disease processes can be difficult. In this manuscript, the most salient aspects of AD and bvFTD and the key signs that might contribute to differential diagnosis of the two disorders are highlighted. Proper diagnosis of AD and bvFTD has important implications for treatment because there are symptomatic therapies for these two types of dementia. Additionally, their appropriate identification may contribute to long-term planning of the care of these patients.